Don't we already have that in the form of PKI? (Think TLS certificates, PGP/GPG keys, SSH keys, et al)

If someone's posts, articles, videos, interview recordings, etc. were signed with the author's private key, then we could all verify it with their public key.

Of course, there's a technical barrier to overcome but I imagine it would be the same with whatever Obama's proposing here.

Fixed!

I updated the main post. Good work!

Matrix.

Take a look at the Clevo NV41.

I run a local unbound instance, which talks DoH, DoT, etc., and then point my PiHole at that.

I installed Jerboa from F-Droid.

I just moved to NixOS. There's a steep learning curve but if you're a proper geek and value immutability it's pretty bloody good.