I'm not a maintainer but as the quote goes: "I would have written a shorter letter, but did not have the time." I'd suggest you keep a sense of how much effort they've put into packaging their PR to be the minimum change required to achieve its goal vs effort required by you to read it. Reject low-effort or overly verbose work.

IMHO OSS doesn't work if every 1 hr of contributor time spent on a change requires 1 hr of maintainer time to review. Contributor time spent on polishing, tidying and breaking down work is essential, and so maintainer time is a fraction of total time spent on a change.