Mega Pinsir is running EQ solely for Aegislash. Otherwise it would have CC, which is outside of Aegislash objectively better. Mega Tyranitar is running EQ just for Aegislash. Terrakion would have room for other things on Choice sets that it would like to have, such as reliable STABs and Iron Head for Clefable. Also the fact that a CB set is practically unviable solely because of Aegislash's existence. And non-Choice sets could have things like SD, Taunt, Sub, HP Ice that they don't have room for because they need EQ for Aegislash. Dragonite runs EQ just for Aegislash (+1 Outrage does enough to Heatran, and Lum Berry counteracts status), while it could beat Ferro/Skarm/Mega Scizor but can't because it's forced to run EQ to get past Aegislash, or in the case of CB could run Thunder Punch to hit Azumarill. Greninja would be running a Hidden Power (Fire/Grass) to greatly enhance its coverage and potency, or Substitute/Shadow Sneak which are nice options, but is heavily encouraged to run Dark Pulse just for Aegislash. Mega Heracross could run Bullet Seed or SD but must run EQ just for Aegislash. Mega Medicham runs Fire Punch solely for Aegislash. It's objectively true that numerous Pokemon forfeit coverage solely for Aegislash, there's no way you can argue otherwise.
I really can't see how Close Combat is that much more valuable than EQ, given EQ KOs almost everything Mega Pinsir would use CC for. Besides, as I wrote, even if Mega Pinsir would "rather" have CC for whatever reasons, the question is how much it's giving up, not whether it's giving up literally anything. Also keep in mind that even a super effective Close Combat isn't that much stronger than a neutral return, and similarly for neutral CC vs. NVE Return.
So, the only things it really loses by going EQ over CC:
Some damage on defensive Rotoms, who it can't KO even with +2 CC and who can simply cripple M-Pinsir with burn, and who are 2HKOd by +2 return anyway
The ability to OHKO Ttar without a boost. (+2 EQ OHKOs)
The ability to OHKO Physically Defensive Ferrothorn (+2 return OHKOs specially defensive), who still takes massive damage from +2 return and goes down with even 10% prior damage
The ability to do a tiny bit more damage to Skarm, who will simply OHKO in return with Brave Bird thanks to -1 defenses.
Everything else it can simply deal with using EQ or Return just fine. Or it could simply run CC and the player could run something else to deal with Aegislash, and wait to bring out M-Pinsir until it's dead. (Incidentally, EQ is actually better vs. some threats as well, such as Mega Mawile and Mega Manectric.)
Just because this post is relevant to M-Pinsir and appeared as I was typing, my comments are in bold:
Without Aegislash, reasons to use Close Combat:
- It's more powerful. Not much more powerful than NVE Return, actually. See above.
- After a Swords Dance, Close Combat can actually OHKO Rotom-W. It can't KO Physically Defensive Rotom, who can then OHKO with Volt Switch thanks to the defense drop. As for offensive Rotom, +2 Return OHKOs 81.3% of the time.
- At +2, Close Combat can 2HKO Skarmory. Much easier to beat than with Earthquake, much less prior offensive pressure needed. +2 Return can also 2HKO after SR. Even so, it doesn't matter because Skarm OHKOs back with Brave Bird. Actually, that's wrong; it only OHKOs after the defense drop from CC.
- It lets you beat Ferrothorn, Excadrill, and Tyranitar more easily. True about Tyranitar, kind of true about Ferrothorn, false about Excadrill. Even if its Balloon is still intact, +2 Return OHKOs despite being resisted.
Now, Terrakion. Choice sets run dual STABs and...? SE Iron head is only slightly more powerful than neutral STAB Stone Edge (160 vs. 150 BP). Even that aside, what goes in the last slot? Quick Attack? X-Scissor? Just because it might sometimes like to run one of those moves doesn't mean it's realistically giving up much by having EQ. Non-choice loses out on a second support move, I'll admit that, but just because it *could* run two support moves doesn't mean it's suddenly crippled or even just significantly worse by having to "only" run SD or Sub + 3 attacks.
Dragonite might have a bit of a tough choice between Fire Punch or Earthquake, but it's not solely due to Aegislash. He also wants EQ for Heatran (you can't honestly argue that "+1 Outrage does enough" is a sufficient argument when EQ is a swift OHKO at +0 and frees Dnite up to use the much less risky D-claw), Tyranitar, Terrakion, and even various steels like Mega Mawile since SE EQ is a fair bit stronger than SE Fire Punch. (certainly more of a difference than Mega Pinsir's SE CC vs. neutral Return)
Greninja's coverage and utility is excellent whether it runs HP or not. Even that aside, Dark Pulse isn't completely useless outside of Aegislash (it also hits various psychics, especially Slowbro), though I will admit HP Fire is overall a better choice than Dark Pulse.
I'll admit Mega Hera would like Bullet Seed, but it's not the end of the world. It's only really losing something vs. Azumarill, Hippowdon, and somewhat vs. Rotom-W as well. It also hits Keldeo on the switch in, but only on the switch in, since Keldeo frequently run HP Flying which OHKOs Mega Hera (and actually, Close Combat can OHKO Keldeo anyway especially after SR). SD would also be nice, I'll admit that too, but again, not really the end of the world.
Mega Medicham also wants Fire Punch for Mega Mawile, safety vs. Ferrothorn (who frequently run Protect), and Mega Scizor.
And all of this doesn't even address the fact that not every fucking pokemon on a player's team that can possibly run a certain move to hit Aegislash has to do so. There's literally no reason to relegate Aegis duty to something like Greninja when you could simply run one of the multitude of other checks that already love running EQ. Or you can just give bullet seed to Mega Hera and again, use something else to kill Aegis before sending it out. These are all basic coverage decisions just like any others we give no extra thoughts to.
So now, the determination for ban. To me, being forced to guess any number of Aegislash sets with the prospect of losing a Pokemon if I guess wrong, being forced to guess in the arbitrary King's Shield skewed 50/50 again with the prospect of losing a Pokemon if I guess wrong, in combination with Aegislash's general utility and effectiveness lead me to believe it is broken. To deal with Aegislash, I can't simply have a counter. I need to have multiple checks as well as God-Given skill at arbitrarily guessing. I only have 6 Pokemon to win and 24 total moves to use, I can't afford to dedicate so many of those slots to safely handle Aegislash.
If you cannot accurately dispute this, then logically you have no other choice than to have a pro-ban stance on Aegislash assuming you're a reasonable person without a preconceived anti-ban bias.
Except that I can, and I
have (as well as
here and
here), and many others have as well.