The Snap Store, also known as the Ubuntu Store, is a commercial centralized software store operated by Canonical.

Anyone can create APT repositories and distribute software freely. Users can point to multiple repositories and define priorities. Thanks to the way APT works, if a bug isn’t fixed upstream, Debian can fix it with a patch. If Debian doesn’t, Ubuntu can. If Ubuntu doesn’t Linux Mint can. If Linux Mint doesn’t, anyone can, and not only can they fix it, they can distribute it with a PPA.

Although it is open-source, Snap on the other hand, only works with the Ubuntu Store. Nobody knows how to make a Snap Store and nobody can. The Snap client is designed to work with only one source, following a protocol which isn’t open, and using only one authentication system. Snapd is nothing on its own, it can only work with the Ubuntu Store.

This is a store we can’t audit, which contains software nobody can patch. If we can’t fix or modify software, open-source or not, it provides the same limitations as proprietary software.

https://linuxmint-user-guide.readthedocs.io/en/latest/snap.html