I don't mind that in a "proper" text where it's actually useful and fun to read something with a flair. But maybe it has always irked people in short form (forum comments etc), but they've never just called it out until now? I do sometimes read something that gives me an "iamverysmart" feeling, as if the author used a thesaurus to find a synonym for half the words to sound clever but it just makes the whole thing incomprehensible.
Americans famously have a median 6th grade reading age, so words like "delve" and "perspicacity" aren't going to win friends and influence people.
Ironically, AI writing is too literate. It reads like clunky pastiche to literate readers, but it's still using words and constructions less literate readers haven't seen before.