It’s how the anti-fingerprint features in browsers like LibreWolf and Mullvad are supposed to work: make all copies of the browser appear the same, which means forcing some options in the browser settings, so that nobody sticks out. Brave chooses to do so by randomizing some of your browser fingerprint data, which really doesn’t prevent you from standing out, it just means that your fingerprint info the trackers collect isn’t going to be accurate.
I used Sabayon for a bit too. It was basically “Gentoo made easy” with a simpler installer and as you said a binarypackage manager rather than compiling packages from source. It’s wasn’t 100% completely dead after dropping the Sabayon branding, it morphed into Mocaccino Linux, but when they did so they re-based it on Funtoo, which is also now dead.