The sad thing is that often there's an equal mental effort to read GPT articles and the real ones. It's as if people are trying to make their papers as incomprehensible as possible.
Nah--If you're publishing in Nature, you're already well beyond that game.
The incomprehensibility comes from the fact that abstracts (and particularly NPG abstracts) are trying to do many things at once--and all in 200 words. In theory, the abstract should describe why your work is of broad general interest (so Nature's editors will publish it), while explaining the specific scientific question and answer(!) to a specialist audience of often-picky, sometimes-hostile peer reviewers, and conforming to a fairly specific style that doesn't reference the rest of the paper.
It's tough to do well, and even moreso for non-native English speakers.