I mean I know what is generally meant when the term gatekeeping is used but it seems like those that throw the term around consider something as simple as asking what comics they like to be gatekeeping. Is it as simple as that?
I remember when they announced the writers for the Star Wars High Republic series and besides the fact their twitter posts were full of "white man bad" nonsense she mentioned how empowering it was to see a female Jedi on screen. Of course she got mad when people pointed out there were female jedi in the prequels. Her defenders were calling everyone gatekeepers.
Also, there was the lady who is producing the new She-Hulk movie. She got mad because someone asked her if she is familiar with the character because the guy was concerned since so many of her tweets were about how evil white male nerds are and how horrible western canon is. She mentioned something about gatekeeping but I would think it is entirely reasonable to expect someone who is given a comic book related project to know the source material. I am currently on season 2 of Babylon 5 but if they ever did a reboot or sequel and asked me to write for it, you can believe I'll spend at least two months cramming on all the B5 lore I can find.
Sorry for the long post, but I would like your input. It seems to me that those that throw around the term "gatekeeper" are people who are mad because someone may have asked them something pertaining to the hobby.
But what do I know. Entering a hobby/fandom and then complaining about how it doesn't cater to you and insulting people makes perfect sense I guess.
I have a side example. Recently a book about videogames based on Batman came out. It started with games released for the PS3. The talk was passionate on the subject and how much the fans loved the games.
I mentioned to someone how much the NES Batman was a favorite. They had no idea what I was talking about, and thought I was being an old coot for bringing it up.
It was aimed at new fans, but purported to be more than that.
This was an attempt to gate keep the fans, by keeping out specific groups that loved games for it. The accusation of gatekeeping is part of the gatekeeping. Every person using this technique aims their statements as if they have been a part of it the entire time, except someone keeps them back. They then try to get that other group out so then the accuser can become the defacto leader.
I really couldn't tell you much about the book because I realized it wasn't for me.