Originally posted by Sonikku
headcanon: yoshi deletes baby bowser in the yoshi series games so regularly that bowser has childhood trauma attributed to them, so in super mario world he designed his castles to explicitly prevent yoshi from entering hence why we cannot use yoshi in castles
pretty sure he just hates mario for being friends with the yoshies and protecting them which is possibly how mario ended up going to dinosaur land and yoshi's island (the smw one, yo'ster island) in the first place despite them not appearing between yoshi's island and smw if we were to assume yoshi's island happened first and smw is somewhere in the middle of the "canonical timeline"
mario and luigi are just huge yoshi rights advocates, peach and toad are bourgeoisie so she probably doesn't care as long as they bring more money to the mushroom kingdom
im not sure if he ever made amends with them because regardless of where you place the rpgs, im pretty sure he doesnt have a positive interaction with yoshi and the mario kart and party tournaments can be interpreted as him partaking just to win the gold for his countrymen