I would have thought that support for this architecture would have been useful to keep, since a lot of rad-hardened systems (think space, satellite applications) still use it.
http://www.sandia.gov/media/rhp.htm
Those satellites that are going up with the old radiation hardened 386 are going to have to run a version of the linux kernel 3.7 or earlier. I suspect they are conservative with regards to their kernel choice anyways, so that should be okay.
In realistic long term operations, deprecations don't hurt. I.e. your air traffic control system running on PA-RISC and HP-UX doesn't care that HP-UX only run on Itanium now. You keep running the old software and set up some kind of support schedule to keep the system patched during it's service life through the vendor or otherwise.
Besides, when the machines take over, they may want to spare those who respected them ;-)
I hope they feed me and keep my cage clean.
I can't blame them for wanting to drop it though, not only do you not have the full range of atomic operations, but also the MMU doesn't respect the WP bit from kernelspace which means special code in copy_to_user()
I wonder how long they will keep the 486SX alive now that it's the last one that requires 387 emulation.
You've still got all the old kernels that do support it. And Debian certainly has historical archives (http://www.debian.org/distrib/archive) and I'm sure other distros do too, if you want all the other linux architecture.