Alakazam does NOT take special hits at all. Both Zapdos and Raikou hit in the neighborhood of 50% with either attack, and threatens to KO with Thunder. Considering these two are the only true special attackers in GSC, that just about sums the list.
To humor you, let's continue. Starmie does well over 1/3 with each attack, leaving Alakazam the dilemma of either healing or risk being KOd next turn. And let's face it, how often does Starmie ATTACK anyway, it's either spinning away spikes or setting up a screen or paralyzing something. And if given the choice, why the hell would you go to Alakazam when you could go to Snorlax? Furthermore, Starmie walls Alakazam with ease, especially if you choose to go with Encore.
If it does switch in on Gengar, it'll be because the Gengar user wants you to switch into Gengar. If I ran a Drumzard team and used Gengar, I wouldn't mind exploding on zam (one of the few pokemon quicker than charizard, after Raikou/Starmie/Jolteon, tying tentacruel/zapdos) to pave way for a Charizard sweep. And I hardly count playing into your opponent's hands an advantage. Or do you mean the standard IP/Tbolt/Explosion/filler Gengar who gets splashed onto teams as a spin wall rather than capitalizing on its true dangerous element of surprise, who've I've been against since the beginning. A predictable Gengar doesn't deserve its OU title. How often do you still see the "standard" Gengar in play? Because that's a poor level of competition.
Alakazam can switch into Suicune moderately well, not so much if it packs Toxic or Roar with Spikes support though. And like the case with Starmie, who the hell attacks with Suicune? And go to Snorlax/Heracross. Furthermore, Suicune outstalls Alakazam EASILY, who is a 5HKO more than 60% of the time.
Of course there's Exeggutor, who always has either/both LS or/and Stun Spore.
After that, you have your mixed sweepers in Dragonite, Nidoking, Pgon2, and Tyranitar. I'm not going to bother with those calculations, but I guarantee every one of those can hit for 50+% with their special attacks.
In the BL world, you have Houndoom as the best example of a pure special attacker. Alakazam can't switch into any of its attacks... or do anything to it at all really. Then you have Charizard and Typhlosion, whose FB both hit for 50+.
So it would be nice if you stopped passing off bullshit as facts, thanks.
Of course, it can take hits from Umbreon, but what the hell are you doing switching INTO umbreon, who most likely packs toxic? The same applies to Blissey. Furthermore, I've dismissed these two (especially the latter) as being garbage Pokemon, so using them in an argument is rather... counterintuitive. You were advocating Blissey remember? Not very successful apparently, because she seems to be the butt of everything negative.
It's funny you bring in your OWN preferences and pass them off as facts. Stun Spore not being a priority on Exeggutor??? Where Explosion/Giga Drain are? And Forretress carrying HP Bug really a rarity? Does it really matter if Alakazam packs Fire Punch? The topic here is switching in; you're not switching in zam into HP Bug Forretress, and no one sure as hell switches Forretress in on zam unless he knows zam doesn't pack FP.
So really, Alakazam only switches in on... very little without having to recover the following turn. DP from Skarm does over 1/3, BS from Miltank over 1/3 [+paralysis], Surf from Starmie does over 1/3 [who walls zam in return]. And all three of those are utility Pokemon, meaning rarely attacks. And should they not attack, you should have far better options to go to in Snorlax/Marowak/Heracross/Machamp. And switching in, using their switch turn to Recover, is hardly an advantage.
In the land of everything-uses-Rest, running out of Psychic PP is actually the most omnipresent threat for 'Zam, not a particular "counter" coming in to ruin its day.
Post a log of this match and I'll tell you how you played poorly or how Alakazam is a worthless pokemon. It has to be one of two, and I'm giving you the benefit of the doubt by just calling Alakazam no good.
Eggy can't beat Water pokémon or Tyranitar without Giga Drain.
You're using Egg wrong. It's an option, I'll give you that. It should not be preferred though, except in very very extreme circumstances. Substitute (gives you options with sleep and stun, blocks rapid spin starmie, etc), LS (the best move for forcing switches, and works awesome in conjunction with Substitute), Stun Spore (this works on everything, nothing resists it, and para is extremely underrated), Sleep Powder (not so much either, it's not a necessity if you know you'll be sleeping either a ST Raikou/Suicune/something that STs and you can't benefit from it, 04 thinking), Explosion (also not a necessity, that's 04 thinking), Psychic (the hit all attack that doesn't really hit all because Psychic has horrible coverage, HOWEVER, ALL GSC teams are weak to Machamp and hence Psychic is preferred, as well as being the stronger neutral attack to special walls in Raikou/Snorlax), Toxic (Egg is one of the best Pokmon at forcing switches and spikes damage, allowing it to single handedly Toxic multiple pokemon reliably, the only one in the meta that can), and Giga Drain (probably the best attack in terms of dealing damage DIRECTLY, but you shouldn't be doing damage directly with Egg, think Gengar).
Giga Drain's primary turn off is its 5/8 PP. While you technically have the ability to KO Suicune, you won't, because a couple odd switches/mispredictions put you dangerously in out-of-PP territory.
It's even quite arguable that Giga Drain has better coverage than Psychic... Chew on that little tidbit.
It's arguable that HP Fire is the better choice of the three.
With all that said, Alakazam doesn't stand out in the OU meta. In BL perhaps, but too many things can take hits from it and it can't take a single hit in return. Sure it has one turn recovery, but it seems that's all it's doing. There are far better Pokemon that fit the "can't take a hit, but hits hard if given the chance" bill. Machamp is probably the epitome of this. And he hits a hell of a lot harder than alakazam on every front, and more resilient too.
Blissey is still sucking.
Giga Drain is an option (the same way HP Fire is an option), but not a priority. Your team must capitalize on the fact that Tyranitar/Starmie can't switch into Egg (e.g. you're looking to reliably explode on Raikou/Suciune to set up Vaporeon/Charizard/Tentacruel/thundermissy or something), but otherwise, it should never be used as a "general attacking move" for "coverage". The only pokemon that should have moves like these are mixed sweepers, where their only job is to hit shit, a wide variety of shit, hard. Exeggutor does not fit that criteria. Same reason you wouldn't give Starmie/Alakazam 3-4 attacks for more coverage, because it really doesn't matter; they're not killing anything anyway.
"Standard" boltbeam gengar sucks, as much as standard curselax.
And please post some logs. I'm really curious as to the "current level of competition".
EDIT: The majority of GSC wins come from either a lucky CH, freeze, misplays, or just sheer brute force through explosion/physical attacks. When's the last time Zapdos KO'd Starmie to decide a game? Or Raikou Skarmory? Or Marowak Raikou? Almost never. Having Giga Drain won't guarantee any kills against water/rocks, it might prevent them from switching in, but Psychic solves that bit just fine against anything that's not Tyranitar/Starmie. And both of them hate being paralyzed. It also opens up a slot (unless you're recommending no Psychic, in which case 8 PP is much too easy to waste for the opponent and once that happens, he becomes a free switch for low HP rest) for one of the plethora of other support moves Exeggutor can use efficiently.
Of course, there's wins through just sheer outplaying your opponent via toxic/spikes, or in a case of a mismatch, but we're assuming similar competition in a general sense.