One aspect is that the server side is not free software. So only Canonical can reasonably host a repo of snaps.
That was enough for me not to look into the technical merits of the clientside implementation. The few experiences I had with snap was that programs were starting slowly (Firefox) and e.g. GPU acceleration did not work (vlc). Not sure how good the sandboxing is. But I run my Firefox sandboxed by firejail and the overhead can not be felt in daily usage.
Ubuntu has replaced the deb version of Firefox with Snaps a few times on my computer.
On at least 3 occasions, I became aware of this when I would open Firefox and nothing would happen, except a message that "Firefox is already running". The only resolution was to install the deb Firefox package.
A couple months ago, I needed to do a fresh install since my system got borked during the upgrade to 24.04 LTS. As usual, the Firefox snap package was installed, so I decided to give it a try.
To its credit, it actually works this time. However, it will not save images on right click or open Zoom meeting links in the desktop client. I am fairly certain this problem would disappear if I switched back to the deb package, but it's not a big enough hassle for me to bother. I can live with some workarounds for now.
Overall, I don't mind snaps, but the Firefox snap has been far more trouble than it's worth.
That was enough for me not to look into the technical merits of the clientside implementation. The few experiences I had with snap was that programs were starting slowly (Firefox) and e.g. GPU acceleration did not work (vlc). Not sure how good the sandboxing is. But I run my Firefox sandboxed by firejail and the overhead can not be felt in daily usage.