> they abandoned POSIX compatibility, built a massively over-complicated product
This is a wild sentence--how can you criticize them for abandoning POSIX support __and__ building a massively over-complicated product? Making a reliable POSIX system is inherently very complex.
What would go in to POSIX compatibility for a product like this which would make it complicated? Because the kind of stuff that stands out to me is the use of Linux specific syscalls like epoll/io_uring vs trad POSIX stuff like poll. That doesn't seem too complicated?
I think the criticism (just interpreting the post, don’t know anything about the technical situation) is that the complication is not necessary/worthwhile.
POSIX can be complicated, but it puts you in a nice ecosystem, so for some use-cases complex POSIX support is not over complicated. It is just… appropriately complicated.