I think this article is not providing adequate alternatives.

Most programs link against quite a bit more than libstdc++ and you clearly can't expect users to install a bunch of packages to get their program running. Those extra libraries usually take up most of the space in a package. If you include all the shared libraries you need, apart from the system libraries in your distribution, you pretty much have an AppImage already, just as a tarball instead of a squashfs image.

I think GOGs path is not horrible, but it is much less effective at making Linux a viable alternative as a gaming platform. They literally only support Ubuntu 16.04 and 18.04.

It also struck me as odd, that the author was complaining about the complexity introduced by Proton. What is Valve supposed to do?