NetBSD i386 bit moved to a 64 bit time_t and they added some logic for 32bit time_t binaries to still work.

OpenBSD i386 went to a 64 bit time_t real soon after NetBSD did.

Both OpenBSD and NetBSD should not have any 2038 issues on 32 bit systems.

FreeBSD i386, I do not know.

Linux 32bit just finished the move in the past year or 2. I do not how complete that is. But I suspect it will be fine.

Others, I have no idea.