I think this is good. However, my impression from trying to install more complex projects is that a main issue is a cultural one: Python package developers are

I think this is good. However, my impression from trying to install more complex projects is that a main issue is a cultural one: Python package developers are happy to introduce breaking changes if they think they will not break for too many of their users. For example there are packages which transitioned to being python 3 only without changing the package name, or changing the version major number. This breaks the assumption that packages use semantic versioning, which many tools use. And that's arguably less of a problem for that shiny new startup company which will, with 95% likelihood, have gone bust five years from now, and also not for the FAANG companies, but it is a big problem in scientific institutions which do not have money or personnel to constantly rewrite their software.