Yep, several projects I know are leaning into AppImage to get around dealing with installers. The biggest problem with AppImage is that it _is_ just a binary, so things like desktop shortcuts don't come with it. AppImageLauncher does solve this issue (and create a "canonical place" to place your programs, like /Applications/ on mac).

I do agree it's fragmented and frustrating where we've ended up for installers. My main critique is more that the state of linux packaging _isn't_ what thunderbird is doing here.