“Provides more security than windows”
This is the only one I seriously doubt.
Ms defender is actually something I wish we had a replacement for.
Read only root fs is a start, but it doesn’t protect my documents.
Like your linux doesn’t get hacked because no one cares, if we become a target we are helpless more or less.
The all flatpak thing took me aback but, you are right the app maintainers fix their stuff there first.
Solid advice.