This almost never actually worked in my experience. It was more of an annoyance than not even pretending to work, because I'd take time trying to get things to install in the UI and they wouldn't work before I eventually needed to revert to CLI.
My experience mirrors yours. Could never get double-click on .deb to work, same symptoms, and Software Center was always buggy/frustrating. dpkg -i all the way, but that's definitely a ux hit for broader adoption of Ubuntu.
Ah... I want to like Linux. I really do. But I regularly install software across MacOS, Windows, Debian, and CentOS, and the only time I have trouble installing is for .deb/.rpm/.snap.
Installing on Windows is run the installer and click through the guided wizard. Annoying, but it works and it’s foolproof so whatever.
Installing on MacOS is unzip and click and the application is already running. Drag over to ~/Applications if I want to. Easy as fuck.
Installing on Linux is trying to remember what apt-get/snap/dpkg/etc. I need, then on top of that what --dangerous or --classic or I don’t even know what all else I need, and cross my fingers and hope it works. It’s honestly aggravating.
