rclone - you can use cheapest cloud or s3 provider and sync encrypted data. Syncthing - sync across devices.
Engineers did that. Zuck just saw no business advantage to keep it private. He agreed to open-source them to popularize whatever they build in Meta to make hiring engineers easier, since they already know whatever they use inside Meta
Adguard is good, very good. Their rules are default included on uBO, they know their jobs well so getting very good product. As an alternative you can consider NextDNS
There is sponsorBlock version as well
Mullvad, iVPN
Nope. And you shouldn't as well
I said I moved back to LibreWolf (Firefox fork)
How they will depart from crypto/Blockchain BS
How this can be used to improve OSM/Organic Maps?
Use Firefox. Brave is Chromium. Brave's crypocurrency stuff is shady, I need a browser not a crypto. uBlock (arguably the best extension) properly only works on Firefox. There is LibreWolf (Firefox mod) if you want ready to use, hardened browser.
Use rclone crypt with any provider