That issue is related, but not quite what I meant. I would want the app to be updated in the background whilst it is running (which works fine for APT installed packages), so just closing it and re-opening it would get the newer version. That bug you linked to is the issue that after getting a visual prompt about a newer version of Firefox being available, the "snap refresh" isn't run immediately after closing it down. Having to close an app to update it reminds me of the pain of Windows updates.

You're technically correct (the best kind) about them not removing alternatives, but you have to do some manual intervention to get them back, so I consider it being removed when compared to the previous behaviour of having them available by default.