Regardless, I don't care about profiles or any of this other stuff, but I don't begrudge the author for mentioning things that aren't up my alley. In my mind, when I read a list-based article, I don't expect everything to be relevant to me.
As for my information, I'm comparing the install base for TST with that of uBlock Origin (both only counting Firefox). It's not a perfect measurement, since not all Firefox users have uBO either, but it should if anything overestimate TST's relative popularity.
Tree-style tabs [0] has 163,716 users.
uBlock Origin [1] has 6,175,439 users (only counting Firefox).
That places TST at about 2% of the install base of uBO, which is plenty small to justify my saying that most Firefox users (and prospective users) don't care about TST.
[0] https://addons.mozilla.org/en-US/firefox/addon/tree-style-ta...
[1] https://addons.mozilla.org/en-US/firefox/addon/ublock-origin...