Why is Ash's Pikachu (Partner Cap) weak compared to other Pikachus in USUM?

Question

Apparently Ash's Pikachu's power is undeniably strong, due to their bond over the years and adventures (and yes, anime logic...) However, Cap Pikachu seems to be very frail but good of a sweeper. In the anime, however, Pikachu is shown to be very tough to beat, even with moves like Guzma's Golisopod's Poison Jab, even when poisoned, it's shown to have survived. How?

Answer 1

This is simple anime Logic. Think about it, how entertaining would the anime be if Pikachu constantly got OHKO'd or 2HKO'd by every opponent Ash faces? It would get rather boring (or entertaining depending :p) to constantly watch Ash Lose. Now, let's look at this from an in-game perspective. How OP would it be to a Pokémon like Ash's Pikachu on your team? A potent sweeper who could deal plenty of damage and take plenty of damage like you mentioned. It would be On every competitive team if there was a Pokémon like that. So now that we have covered that, Game Freak probably had to compromise. They allowed Pikachu to be a Sweeper, albeit with a Light Ball. They let it be not as bulky as in the anime because that would be OP. So, that is why Pikachu isn't stronger than every other Pikachu. As for how Pikachu survives Poison Jab while Poisoned, that is complete Anime Logic. Hopefully this helps.