What is really not nice is the obession with pruning the versions for each package. For a specific package, there is no serious issue with keeping several old versions hanging around in the package tree. By default the package manager understands that and the user doesn't see them. But where there is some compatibility or build issue, the user would have the option of masking the latest and keep going on an earlier version: it would still build, usually with no extra effort. It would rebuild fast if you have a build cache. You could downgrade easily if you discover an issue weeks later.
But no: most maintainers where that matters delete the previous version as soon as the new one is half in. Not a helpful obsession.