Teppic

In time it may become a trade-off between new (with associated features and speed) Vs tried and tested/secure.
To us now this sounds perverse, but remember that NASA generally use very old hardware because they can be more certain the various bugs & features have been found and documented. In NASA’s case this is for reliability. I’ll concede ‘brute force’ does add another dimension when applying this logic to security.

This may also become an AI arms race. Finding exploits is likely something AI could become very good at - but a better AI seeking to obfuscate?

How long until US bans code from developers with ties to CN/RU?

That won’t happen because it would effectively mean banning all FOS which isn’t remotely practical.

No Mint pretty much just works.
Great thing about Mint (or most Linux distros) is that you can try it by booting from a usb stick - see if you like it that way.