Comment by toast0

Some people would rather have an abstraction over io_uring and kqueue rather than choosing a single API that works everywhere they want to run, choosing to only run on the OS that provides the API they prefer, or writing their loop (and anything else) for all the APIs they want to support.

But I agree with you; I'd rather use the thing without excess abstraction, and the standard apis work well enough for most applications. Some things do make sense to do the work to increase performance though.