The security sandbox provided by snap is a major point to allowing packages “from anywhere” that you don’t necessarily fully trust. Like 3rd party vendor packages. The deb installer runs the package installation of debs as root and it allows them to do anything. I’m not even talking about running the software, a deb can run anything and do anything to the OS at install time. Its security model requires trusted repositories where someone gatekeeps what packages can reach your computer. Snap had the sandbox design since its inception to solve this problem. It wasn’t something tacked on later.

The Firefox snap rollout was a shit show. The snap package itself had defects such as lacking important performance optimizations that were done in other snap packages for example. Then there was the update notification that bugged people to close the app only to show again if they reopened it soon after. Those were ultimately solvable problems but Canonical let them trickle into most users’ desktops during an LTS release… And this was many people’s first impression of snap - those few annoying bugs - even if the system has been solid and running, solving real use cases for years prior. A.k.a. a shit show.