[throwaway129013]

> I don’t see why the package manager should prevent using it with another library that depends on a different version.

I do. The main reason for Linux distributions to exists is to provide a development and running environment where:

- API/ABIs do not change for the whole lifetime of the distribution. No new features, no new bugs, no new vulnerabilities, so that your production code can run reliably for 5+ years.

- Vulnerabilities are fixed with minimally invasive patches.

- Vulnerabilities are fixed in reasonable times even if the upstream development stopped. Patches are well tested against the set of packages in the distribution.

You simply cannot have these 3 features together if a distribution ships 10 different version of each library.

It's already a ton of work to maintain packages in stable distributions.

[wtetzner]

I’m confused by your comment. This is about a programming language package manager, not an OS package manager. Or was that just an example?