Snaps per se are no better or worse than flatpak. Canonical's mistake, IMO, was to make their store the only place snaps can be hosted. That is the "proprietary" bit everyone keeps talking about.
But in practice even for flatpak the only realistic place you can publish your flatpak if you want any traction at all would be flathub, so both formats have only one store right now. But flatpak allows a custom store while for some strange reason Canonical decided not to allow snap that freedom.
Yes, I agree. Snaps or Flatpak, not much of a practical, technological difference. What sets them apart is the way the distribution is handled, including the open source availability of the backend, which enabled for example Red Hat and Elementary to run their own stores.
If you are making your own distro, creating your own flatpak store is trivial, that's all what matters. Linux Mint doesn't use snap exactly because Canonical forces everyone to use their snap store.
Another problem is, Canonical promised to release server components and enable alternative stores, and just forgot that they made that pledge.
Also, rugpulling users and migrating things to snaps without asking their users in order to "create a positive pressure on snap team to keep their quality high" didn't sit well with the users.
> But in practice even for flatpak the only realistic place you can publish your flatpak if you want any traction at all would be flathub
But, for any size of fleet from homelab to an enterprise client farm, I can host my local flathub and install my personal special-purpose flatpaks without paying anyone and thinking whether my packages will be there next morning.
Freedom matters, esp. it that's the norm in that ecosystem.
I was neutral-ish about Ubuntu, but I flat out avoid them now, and migrate any remaining Ubuntu server to Debian in shortest way possible.
I'm using Debian for the last 20 years or so, BTW.