In the interest of playing devil's advocate a bit, I think that ESAM may have the right idea with his character. What I mean by that is his view of Pikachu being so high has a positive impact on his mindset. He's not too far off, either. He said himself that Pikachu doesn't lose to any of the perceived top tier characters (Sheik, Diddy, Cloud, even ZSS, Rosalina, Fox) So the character clearly has some relevance in high/top level play. (He does lose to a few high tiers like Mario, Ness, and Meta Knight, which is relevant as well. Corrin covers those three quite nicely, though, I gotta say.)
So, as a player you can look at this spread and think, well, Pikachu is okay, or you can think like ESAM, "Nothing should be in my way." Even if his MUs with top tiers are mostly even, he realistically has a very good shot at taking on any of the top threats in the metagame. That's if you don't let losing to some slightly worse characters get in your way, and he chooses not to. It's the better way to play, honestly.
The issue lies in the fact that he takes his warped view of the character and shares it outwardly. He's an authority on the game and on Pikachu, so his opinions get more traction than even he might be expecting. That or he legit thinks Pika is top tier. What a nut. I do think Pikachu can be considered an anti-meta character again.