For secure private transfer use the Warp flatpak in Linux and Worrmhole William in Android.

The amount of times I've seen people request help because Pi-hole was not blocking/functioning properly, well a hosts file just ensures nothing leaves that you want blocked. Besides, you may have different machines set up to be strict or permissive depending on their use case.

Absolutely. These lists are created by server admins who collect what the firewall rejects, much like you see with the Pi-hole. They'll automatically block some ads and many threats too. Another tip if you're using Librewolf, Mullvad browser or Firefox with uBlock, enable more of the filter lists.

Use both.

That's a lot of progress! Worth the read.

Pi-hole is OK, but for good measure it's easy to set up a "hosts" file that blocks all that stuff locally. You can use your findings from Pi-hole. On Linux you just pop your entries in /etc/hosts, or other OS equivalent. Here are some curated lists. For Mozilla telemetry - https://github.com/MrRawes/firefox-hosts/blob/firefox-hosts/hosts Massive list for everything - https://github.com/StevenBlack/hosts

Posteo has been stable, professional and functional for many years. Tuta is another good choice.