This is probably the biggest barrier to mainstream linux adoption - devs have to choose between supporting 5+ package formats or just say "screw it" and make a windows/mac app instead.

This is my own opinion, but I think Flatpak and Flathub need to be universally adopted as a standard. It's already growing that way organically, even if major distro projects haven't recognized it yet.

This has its pros. If all agree to use, say, deb, then some of the users will complain, "I downloaded package XYZ from Arch and it doesn't work on Fedora!"