Melee is balanced though, there are no overpowered characters, and all the viable characters can hold their own near equally. The answer to Kirby being underpowered is to simply not play Kirby, there's no easy answer to Steve being overpowered.
Oh bull, the top eight are so objectively better than everyone else that yes, they are in fact overpowered. You whine about balancing but then turn around and say ignorant stuff like "the answer to Kirby being underpowered is just don't play Kirby!" You hypocrite. As if it's not 100% on the devs fault that Kirby is under tuned.
The answer to Steve being overpowered? Why, just don't play Ultimate! Do you not see how ridiculous that is? At least in Ultimate a much healthier chunk of the roster is at least somewhat competitively viable. We don't get the same eight characters filling up every tournament roster. One character being overturned is more than easy enough to solve: you ban them. Simple as that.
The almighty golden child Melee is as grossly unbalanced as the rest. Having a smaller roster doesn't save it from that. Besides that, we love in the age of online patches, so your excuses about "b-but it'll be hard for them to balance a big roster!" are as pointless and wrong as your insistence that Smash is bad just because you don't personally enjoy it. Heck, there are even players making waves in tournament brackets with low tiers in Ultimate. It is an objectively better balanced game than Melee. Yes, the game with almost 90 fighters is better balanced than the one with 26.
"All the viable characters can hold their own!"
And that's the problem. There are eight viable characters in a roster of 26, less than one third can hold a candle to each other and everyone else is so pointless to play you get laughed at for picking them.