If i understand correctly, this is the kind of problem Flatpak and Snap can solve. As a developer, relying on a distro's provided packages just seems too cumber

If i understand correctly, this is the kind of problem Flatpak and Snap can solve. As a developer, relying on a distro's provided packages just seems too cumbersome - there are 10s of distros all with different versions of your dependency and different packaging systems. I guess the only way to distribute a Python application today that works across distro would be to basically build a single application that works simultaneously on many different python versions, not to mention the shared C libraries and other system software used by important Python packages. What do you do if you use psycopg2 X that needs libpq-dev version between 1 and 2 but the distro bundles in an incompatible version of libpq-dev Y? You have to now support 2 versions of libpq-dev across the project, and all dependents of libpq-dev such as psycopg2? The shared dependency model is just too complex to work with, and we have enough disk space that its not really necessary anymore. Sandboxes seem like the way to go.