There’s certainly no way around it when downgrading - as I mentioned above there’s simply no guarantee that files created by a newer version can be used on an older version. (If I had to speculate, there’s probably some config file setting in the newer version which the older version doesn’t understand and hence fails to start up).
For production supported platforms (which Ubuntu is one of), upgrading is supported (within some limits of how far you can go in a single “jump” - see Upgrade Matrix