[KronisLV]

> The lesson that I take is that all non-essential packages should instead be in an official, separately versioned, stdlib.

Hmm, honestly, this is a really great take. A thin OS base, with the "batteries" being optional. Or at least being to use specific versions, bits and pieces from various points in time as needed.

Of course, this could turn into an Eldritch mess, but then again, it might also lead to working software over not being able to update the stuff you want to update because the rest would break otherwise.

Overall, there's probably a lot of consideration to be made about the details, but that seems workable. Stability might still sometimes be an issue (e.g. should the language internals change, a la Python 2 to 3), though i'm not sure whether that can even be addressed all that well, at least in the higher abstraction level languages (with separate runtimes like CLR, JVM etc.).