Well, the Python community is a few orders of magnitude larger than the Common Lisp community, so more of a tempest in a teapot situation here.

This seems like a very minor thing in comparison. The python 2 to 3 thing had many big issues. It was impossible to automatically convert code from 2 to 3. It was very complicated to write code that would be compatible with both versions. If one of your dependencies was 2-only, then you had no choice but to wait for them. Meanwhile, with most software being on 2, libaries were incentivized to stay on 2. So there was a chicken and egg issue.

Is there any impending prospect of major CL implementations distributing asdf-devel by default?

"asdf-devel" is just what this post is calling "releases newer than the ones implementations ship," which not only feels like an _incredibly_ slippery definition, but by definition, no, once an implementation starts shipping it it's no longer a -devel version.

I know of at least one distro that forcibly upgrades the ASDF that SBCL ships, though.

:o

And distro behaviour is part of why the only reason anyone recently bothered working on lisp packaging for debian is the requirement for source packages for software shipped in main repo, so for one program someone built enough tooling to replace old debian tooling and build pgloader the way it should be done.

Not quite. The analogy is present explicitly in the gist but the comparison isn't particularly useful for understanding the social dynamics of the situation here.

Seems somewhat less impactful than that, but analogous, yes.