ShootingStarmie
Bulletproof
Stall pretty much died in Gen 4, not Gen 5.
I think we can all agree that the Ape is responsible for single handedly destroying the seemingly "impeccable" SkarmBliss core. Which is why the two saw a DRASTIC decrease in usage in the 4th and 5th generation. The Ferrocent core was created, and for a while many thought it would counter Infernape. However, an Iron Fist boosted Infernape with Life Orb, Close Combat, and ThunderPunch (Yes, people use this set. It's on Smogon, actually.) Gave the core a run for it's money.
It is true that since the core of SkarmBliss has fallen, the usage of Infernape has fallen as well. But with all these Mixed-Attackers running around this generation, (Namely Hydreigon, Mix-Mence, Jirachi, need I go on?) It seems almost useless for stall to even exist. People argue that Hydreigon, and Infernape are barely seen in standard play, but they still exist. It's a simple fact. In a meta-game full of unpredictability, you must be prepared for anything.
Lastly, Stall NEEDS hazard entries to work. Starmie laughs at toxic spikes, and can retaliate with a LO move due to it's versatility. Donphan takes minimal damage from stealth rock, and can always switch on the offensive. And Roar still exists, people. Did I mention that Dragon Teams completely destroy stall? Magnezone KO's any steel if it can manage to trap it, and Haxorus and Kyurem-B have become infamous for their ability to 2HKO nearly pokemon in the game.
All in all, stall is dying. And for good reason. No one likes to lose, and there's no reason to use a full blown stall team in a meta-game full of hard hitting pokemon.
Infernape did not ruin stall in gen 4. Sure it made it slightly harder to stall (compared to gen 3 which was a stall fest metagame), but stall was still imo the most viable team style in gen 4. Infernape had solid checks in Gyarados, Vaporeon, Tentecruel, and Choice Scarf Rotom, that were all pretty common in gen 4 stall. You think because Infernape ruins one popular stall core it suddenly demolishes stall?
Right, onto gen 5. Yes, there was a huge power creep in gen 5, and great mixed attackers came into play, but people actually forget that there was also a pretty big defensive power creep (i.e new dual typings, abilities, and moves) that aided in stalling. Yes Hydreigon and Infernape are still seen in standard play, and I'm not going to argue about how unpopular they are (because despite them being pretty bad in this metagame they are still "OU"). However, I will argue that these Pokemon do have solid checks that are commonly found on stall teams. Hydregion is a pain for stall teams, but that's it's role in the metagame. It's a wall breaker, and it's quickly worn down by LO recoil, sand recoil, SR recoil etc. The choiced sets are much easier to deal with, and have solid counters. While on paper Hydreigon seems like a big deal, in practice it just doesn't cause that many problems.
Infernape also did nothing to stall this gen. Again, it already has solid checks in the form of Latias, Tentecruel, Politoed, and Jellicent, but it's stats just don't match up to the power of gen 5, I don't see how you think Infernape is threatening to stall, when we have powerhouses that are much more threatening.
Yes, entry hazards are the main form of damage that stall wins off of. But you're acting as if Rapid spinners are hard to get around. Your first example (LO Starmie) is walled hard by Ferrothorn, the most common Spikes / SR stacker, and factoring switching into the entry hazards to spin them away, Leech Seed, Iron Barbs, LO recoil, and potential Rocky Helmet, Starmie isn't going to be living for long (and don't tell me that Starmie can Recover, because then Jellicent hard walls it and blocks Rapid Spin). Donphan is a terrible spinner and Pokemon in general, as it's only niche is to provide both Rapid Spin and SR on Sun teams. Donphan is walled hard by Jellicent, as well as blocking the Rapid Spin.
I don't quite understand by what you mean that Roar exists, so I'm going to skip over this part (are you trying to force out the hazards layer? I dunno what you're talking about here).
Dragon teams do not destroy stall. Facing Dragon teams comes down to prediction (which I wont get into since prediction goes both ways, and that's based on the skill level of the players). Basically, if you're using a stall team and you lose to Dragon Spam / Drag Mag, chances are you were out played, or put predicted. And this isn't even the case some of the times, since stall teams even have solid answers to Drag Spam, such as Shed Shell Skarmory, Landorus-T, and Heatran. While these might not be the most viable options for a stall team, we're talking about Drag Mag, so talking about viability goes straight out the window (imo).
You didn't actually post any REAL problems for stall teams. REAL problems are Pokemon that are used frequently in common team archetypes, such as Keldeo, Landorus-I, and Kyurem-B. imo all 3 of these Pokemon are broken, and will hopefully leave the OU tier very soon with the suspect tests (although I'm not sure there's going to be a Kyurem-B suspect test any time soon).
Good day