Literally said they don’t want immutable.
At best, they might have implied it. (But I don’t think they do.) Here are the (relevant) snippets:
I honestly have even been looking into some of those immutable distros (that’s how much I don’t want to be fixing my system. I’m tired, I just want to use my system to get work done)
I was once told by some kind soul to use an immutable distro and setup “distrobox” on it if I wanted the AUR.
OP, another vote for this one.
It addresses your concerns in a wonderful way:
All in all, I think Bazzite is definitely worth a look. Consider installing it and setup to your heart’s content. If -at any time during or after that process- you come across an insurmountable[3] issue caused by its atomic/cloud-native/‘immutable’ nature, then you can check it off your list and look elsewhere.