Why would you need to block apps installing from non-Play Store sources? You shouldn’t be plugging your phone into mysterious USB ports, and the OS should always prompt you before installing a local .apk file. If you’re savvy enough to use F-Droid, you’re savvy enough to not need that hand-holding “safety” feature.

I mean, it’s about as permanent as you can get within the US’s political system. It’s not really up for “interpretation” like Roe v. Wade, it’s literally just “the State Constitution has changed so this law is now unconstitutional”. If a future judge(s) were to overrule this, it would be blatantly and objectively partisan, which is a much bigger deal with state courts than it is Federal ones

Ive never had to download a codec to use VLC, it should come built-in with every codec you may reasonably encounter on commercial DVDs.