Does it mean that apt will then install a non-snap version?
I haven't verified that, but considering that nothing suggested that I was installing a snap app (other than me not paying attention to apt's output, I guess), I'm not sure if that's even possible. I was planning to stay with 18.04 LTS and then move to something else, but seems like either snap was there already or it has been added after I upgraded.
I don't think so because some apps are only available as snaps. that is less true for 18.04, but 20.04 and 22.04 use snaps fairly heavily and some like firefox only available through snaps, although there is also PPA and flatpaks available.
No, it removes the entire snap ecosystem from your machine, including the snap backend to apt. It does mean that installing snap-only packages becomes more problematic, but that's a price I'm willing to bear.
I think you have to use snap (I can't recall the incantation, snapctl??) to remove the snap mount points (which I think are made when snap packages get installed) first otherwise they don't get removed by simply removing snapd. Only did it once, so far.
