starcraft has 3 factions
overwatch has 23 characters
hearthstone has 32 decks(?)
guild wars 2 has 9 professions
world of warcraft has 12 professions
i'm sure out of all that there's tier lists of what's good and what isn't, but because there's such a minor amount of choices in all of them, "bad" characters can still be useful in niche situations, and it's much easier to balance a small amount of characters over 133 characters
in league of legends, there's multiple characters that can fit into niche counterpick positions (poke adcs such as cait, ez, corki, characters with hard engage such as naut, hec, vi, tanks with huge cc such as sion, shen, leona, you get the idea), whereas in a game like overwatch though, if you need a long-range character for getting picks, you've got hanzo and widowmaker, and then you have to choose between a closer-ranged, more utility based character or a much longer ranged character meant almost exclusively for taking out priority targets. you don't have a large amount of choices for either positions, you've got one character for their specific playstyle
the only one that comes close to league's character amount is dota 2, and only seven out of 110~ weren't picked in dota 2 championship, and that could just be because dota has a much more "unique" cast of characters that can fill very specific niche picks or can be good in a broad range of compositions
i also did say nearly every competitive game, not all of them