Arch Linux also recently announced phasing out the 32-bit distribution (though multilib will still be available).[1] Perhaps the start of a trend.
[1]: https://www.archlinux.org/news/phasing-out-i686-support/
[1]: https://www.archlinux.org/news/phasing-out-i686-support/
Multilib means you can still run 32-bit binaries. Although given Linux doesn't have a stable ABI, I haven't found that 32-bit Linux binaries age well (e.g. if you run something from 10 years ago, it's probably using OSS, enjoy trying to wrap that to alsa...).
Arch is deprecating the i686 only distribution. Which IMHO is a good idea. Multilib support is generally excellent, and to my knowledge no one who is shipping i686 systems (e.g. industrial PCs with a 10 year availability) is using Arch Linux anyway.