[pm215]

It's actually still pretty heavily used in some niches, which mostly amount to "running legacy binaries on an x86-64 kernel". LWN had an article recently about the Fedora discussion on whether to drop i386 support (they decided to keep it): https://lwn.net/Articles/1026917/

One notable use case is Steam and running games under Wine -- there are apparently a lot of 32 bit games, including still some relatively recent releases.

Of course if your main use case for the architecture is "run legacy binaries" then an ABI change is probably inducing more pain than it seeks to solve, hence the exception of it from Debian's transition here.