People always say he has crazy combos or crazy moves or crazy data but to me it sounds like they're looking at it from a vacuum. Pikachu's hitboxes or combos or even frame data are not that crazy compared to some other characters. Even the sum of all his good parts is outclassed by some characters IMO.

Here are the best parts of Pikachu imo:

1. Probably the best zone breaking in the game with tjolt
2. Above average recovery and edgeguarding
3. Good movement and small hurtbox

To the degree of other characters, he doesn't have spammable combo starters, safe huge aerials, easy kill confirms, good disjoints... But I might be wrong and he might be better at some of these aspects than I know. The same applies to everyone else, no one can foresee everything that character or players can do. Which is why there is nothing wrong with seeing characters that aren't as common like Pikachu as better than their results, because it's good to be cautious.