git gud
Yoshi has some weakness that really hurts him. His grab game is high risk/low reward, doesn't have much true combos, struggles to land kill moves, has a mediocre neutral game and all of his moves are unsafe on shield except a well spaced Fair which has 20+ frames of ending lag.
The reason Yoshi is so much better than Dr. Mario is because Dr. Mario is a really bad character and strong candidate to be one of the worst characters in the game while Yoshi is probably top 15. There's no reason to want Yoshi nerfed when he already struggles against some of the best characters in the game (Sheik, Diddy, Sonic, Pikachu, Luigi and Mario).
Yoshi is only "OP" in low level competitive play because he's good at punishing mistakes, but at high/top level play he lacks important tools that the better characters tends to have, such as kill options (Diddy Kong, Luigi, Ness, Rosalina), good neutral game (Sheik, Diddy Kong, Rosalina, Sonic, Mario) and follow ups (Luigi, Ness, Sheik, Diddy kong, Mario)