Yes, I think the only somewhat big distro that still has x86 support is Gentoo.

A bit more niche but Slackware (both the 15.0 released version and 'current' development version) have x86 support (i686). Void Linux and antiX Linux also provide i686 isos.

But, yes, we are in the long tail.

Alpine Linux supports x86-32.

It's the basis of Docker and has tens of millions of copies in production use.