'solo queue players would rather bitch about how unbalanced a champion is rather than learn to deal with them' falls firmly under 'not riot's problem'.
kat has clearly defined weaknesses that pro players exploit to make her trash in pro play. Solo queue players could learn how to do those things and have the same result, but they would rather blame kat being unbalanced and their team being bad than do it. 'my team ignores pings' is not a reason to not learn how to ward properly vs her or lane properly vs her.
Why bother balancing the game at all!