@Dark
Understandable points but there are some issues with some of that:
1.) Snivy. Seemingly is a well trained one right off the bat (it already knew Leaf Storm, which it can't learn until its at least level 15). Not like it was a baby one. Besides which, we need to remember Pikachu was heavily weakened by Zekrom. Literally the minute Ash and Pikachu step into Unova Zekrom zaps Pikachus power away. Besides which, it was addressed to simply make different keys for Pikachu like it was in the Necrozma thread for S/M, but I don't wanna go too off topic.
2.) Im pretty sure Ash beating any champion level trainers was considered outlier before Diantha and Ash-Greninja was a thing. Had not for passing out, Greninja and Ash could have fairly done even better than they did. And IIRC wasn't this Kanto or Johto Ash? Of course inconsistency like that would happen early on.
3.) As far as team rocket go, they are incompetent but that doesn't neccesarily mean they are naturally weaker than the rest. Sans Weezing and Arbok, Team R have given their pokemon good amounts of training to keep up with others. Cacnea for one. Plus it depends on the pokemon in question. Their pokemon like Wobbefet, Swoobat, Yamask, or Mimikyu are pretty strong but stupid reasons prevent them from being consistent threats (Wobbefet only good for countering moves or Mimikyu being serious only against Pikachu. Or just Beware in general). Same thing goes for Ash using Buizel. Incompetent yes, but that =/= being weaker, just a weakness in judgement. And Ash of all people have gotten out of type-advantage/disadvantage scenerios many times and came out on top.
4.) Axew wasn't first stage level, it simply chose not to evolve. There's multiple pokemon like that in the anime (Pikachu, Piplup,) it can simply be strong for only being first stage. Plus I think you might be tad overselling Axew. The best it did to Cynthia's Garchomp was push it back a bit and that was through Axew learning a new move. Plus it was just a practice battle to see how much Axew compared to Garchomp. Obviously Axew would've been stomped in any level of seriousness taken there.
5.) I actually have an issue with "Pikachu damaging Arceus". What damage was actually even seen? It appeared as though Arceus just shrugged it off fairly easily like nothing. Its the same thing as Superman being suceptible to magic. Not having a defense for something is one thing. Being weak to it is another, and the former works here for Arceus had no plates to negate electric attacks. The other stuff is just easy PIS inconsistency for so many reasons, so Pikachu being able to "damage" Arceus shouldn't even be true.
6.) The Type Null/Sivally stuff was already addressed in the Necro thread though. Unless something like Zekrom happens again for Pikachu, there's no reason why others cannot scale, they just simply need separate keys as someone mentioned. And it's not like Gladion and Type-Null will be actively fought by fodder. Gladion doesn't even use Type Null against anyone other than Ash, he uses Umbreon or Lycanroc against fodders (and still stomps them).
7.) Team Rocket being gags shouldnt shut down them being strong, they'd just be like Popeye or Bugs Bunny. Gag characters can still have feats. And for Ash, how would him being a superhuam even be a gag? There's billions of times where Ash shows off super-human strength, a few time thing in S/M shouldnt discourage that.