The problem with Claudish isn't that it's technically poor English, the problem is that it's information-sparse waffle most of the time. It's like dealing with a colleague who needs several paragraphs of tedious preamble to make a point when you just want them to spit it out and be done with it. It also does a great deal of vague gesturing at thoughts without actually instantiating them directly, for example by using the same tired metaphors to the point they don't actually convey a thought any more.
If I say Claude talks like a meringue it's patently obvious what I'm trying to convey, sweet but full of empty space. If you hear that same metaphor day-in day-out then after a while it doesn't call up a thought at all, it's just an annoying verbal habit.
All those complaints about Claude language use make me think we're finally seeing the consequences of a generation growing up on instant messaging.