I use flatpak because I enjoy the sandbox as well. Nice to know that a zeroday in some obscure internet-enabled program won’t automatically grant the hacker access to my entire home directory. And as for xbps-src, I might as well submit my package to the official repos while I’m at it. Don’t get me wrong, I do want to eventually contribute to Void’s repos in some way, but when I have time for that. And right now, I don’t have time to essentially become a package maintainer just to be able to use the apps that I need to use.