Whyyyy did they make kev dumber and dumber?

Rewatching the series…again…cause I do love it. But I gotta vent about how kev’s character was just getting dumber and dumber. And it’s fucking annoying and unrealistic. Just watched episode in S11 where he rolls up to the park and is bragging about his money and flashing his new truck. No guy from a place like Southside would ever do that. I didnt mind that he was illiterate and “book dumb” but in the earlier episodes he was more serious, sexy and street smart with a dash of goofiness. But uggghh they make his character in the later seasons kind of a joke and it pisses me off. Rant over.