@sackofbones@nina_kali_nina@jessienab At least looking at syscalls(2) manpage it doesn't looks like there's been much recent activity there outside of entirely skippable ones (like I disabled stuff like io_uring support on my gentoo machines).
So I think I'd more expect slight compatibility issues due to different behavior rather than missing syscall support. (That said there's also the pain that are ioctl, fcntl, …)