[fn-mote]

I'm not sure what you're referring to, but I would not give anybody good odds of booting from a snapshot on Ubuntu/ZFS.

I would expect that booting from an older kernel would work, possibly in recovery mode.

[tombert]

I have booted from snapshots on Ubuntu with ZFS plenty of times and it has worked fine. I've also used Snapper with btrfs and restored from backup and it's worked fine. I've also booted from snapshots in NixOS and it has worked fine. I actually cannot think of a time where any of those examples didn't work fine.

Windows system restore has never worked for me.

[simonask]

Setting up any of that is well outside the reasonable expectations of the average user.