I mostly agree here.
Although; I have a slightly different experience as well that makes me highly distrustful of people who tout being 'sapphic' as well; as I've seen quite a few people who identify with that label participating in the same kinds of toxic and exclusionary behavior that the self labeled 'lesbians' that are referenced in this article are participating in.
In general; excluding members of the rainbow who are less numerous than our identity group is; is in fact punching down on them and is not cool. If you bear any label in the whole spectrum; you should at least try to know better, and reject exclusionary behavior.
Of course people will be exclusionary to the extent they can get away with it. Don't let them get away with it when you see it. Call it out and educate them kindly if possible; especially those who should know better.
As someone who is as deeply queer as she is transfeminine; I do experience some strange bouts of gatekeeping; especially around people who think I am inherently less feminine than they would prefer.