i fail to see what problems we've solved. it seems to me we've just duplicated the problems of competing packaging standards across distros, except now they all take up more resources and disk space than before.
it may have made a couple of devs lives easier, but the average linux desktop now is messier than a Windows XP SP1 desktop. We have apps from official repos, downloaded DEBS and/or RPMs, flatpak apps, appimages that dont' integrate into menus, snaps (if you're locked into Ubuntu), maybe a docker image or two. Nevermind half these apps are probably Electron based regardless of their crappy packaging.