I have to agree, and its a piece of software I think a lot about. It doesn't do anything particularly special, if you look at the list of features you could list off many others that do the same, and many do much more.
I like cli software, and should be drawn to beets, but yet...
but yet, i still paid 20 for mp3tag and i would do it again
Idk what you mean by "Linux app" but I use beet[1] and it's superior to any manual tagger software I've used.