Note that the glibc release mentioned there (2.32) has been released only two months ago (https://lwn.net/Articles/828210/), and its release notes don't mention time_t now being 64 bits. The glibc manual page linked to by that answer (https://www.gnu.org/software/libc/manual/html_node/64_002dbi...) says "at this point, 64-bit time support in dual-time configurations is work-in-progress, so for these configurations, the public API only makes the 32-bit time support available", which probably means in practice that 64-bit time_t is still not available for common 32-bit configurations (unless you want to lose binary compatibility with all existing software). I haven't been following this Y2038 work, but it's probably been postponed for a later glibc release (perhaps even the next one).
No, on 32-bit Linux systems, time_t is 32 bits (except perhaps on newer ports like 32-bit RISC-V).