The Python community, being relatively small, seems to dig this aggressive way of making changes to libraries and the interpreter itself. It has many advantages and speaking of disdvantages, most of the ones you specify are really non-issues.

I mean, you're not forced to use the newest version of the interpreter. You're not forced to use the newest version of any library. Moreover, you're not forced to use a single specific version of the interpreter on a machine. And with the use of virtualenv or buildout, you won't complain that your application used to work, and it doesn't, because the environment evolved.

And if you're "scpying directories" between servers, relying on whatever version of the interpreter you find, you're doing it wrong.