I'm a recent refugee from ubuntu LTS's, after having run them for a decade or so. Previously, I just never really had a reason to move away from the community support and google-ability around ubuntu, plus many guides having example commands for ubuntu installs etc.
Snaps are what made me switch. It's insane that they're making apt packages pull in snaps. If snaps were an additional thing similar in spirit to `/usr/local` where system admins could install weird stuff they needed that didn't fit, that's one thing. Forcing them onto me is another, especially when you can literally feel the difference between a program living in a snap vs one installed normally.
This is nitpicky but I also don't like that it messes with my mount and df outputs with a bunch of mounts I don't care about and 100%-full filesystems.
Now, debian - I don't know why I didn't make this switch ages ago! It's everything I wanted from ubuntu without any of ubuntu's opinions. My new default linux distro for servers. (I still run Arch on my laptop).