About half of those guy apps you're presenting are irreplaceable. The other half are not. GIMP, Paint, Photoshop, Lighttable, VLC, LuminanceHDR, Blender, firefox, chromium (image/video viewers/editors, web browsers) are all about looking at, creating, and modifying things that are graphical in nature. Thunderbird, a mail reader, is about looking at things that are textual in nature. Same with file explorers, archival tools, and text editors. These things work fine with a cli interface. Unreal/unity are a bit of a special case -- there's nothing that does exactly what they do from cli, because that's impossible, but it's more than possible to create large playable graphical video games directly with a text editor and a cli -- even if it's not possible to play them that way.