Same for surpass and boast, I think I use "surpass expectations" and I had to think for a moment, I would use 'brag' these days but pretty sure in school I learned boast, which sounds more formal BE to me, but of course I'm just guessing here.
ChatGPT, of course, behaves like its training set...and the majority of that set is professional writers' published works, which would be more likely to use words like that. It's a collision of academic and literary writing styles with the expectations of people who think Harry Potter or the New York Times (which specifically targets a fifth grade level, placing them above other papers) are challenging reads.