I just realized that a majority of A tier are filled with characters that have sex kick nairs. The issue I have with this is that it seems like the only reason that most of them are only up there solely for being an extremely solid combo breaker. While that is a fantastic trait for a move to have, I don't think it justifies rating it highly. Imo, I think a move has to have more than just one use to be deemed great.
Take Fox's nair, for example. Not only is it a combo breaker (4 Frames), but it also is one of the main parts of Fox's combo game, as it leads into many of Fox's other combo starters or KO moves.
Another example would be Ryu's nair, which serves a similar purpose to Fox's, being a combo breaker, starting up some of his combos, with an addition of having incredibly low landing lag compared to every other nair in the game. (I personally think this should also be S).
There may be something I am missing here about the sex kick nairs, but as of right now, I don't think just being a combo breaker is a good enough justification for instant A tier.