It's always a challenge to write on topics like empathy and ego because of how heavily they are steeped in your own experiences, both professional and personal, and especially to do so without falling into the same ego-driven traps you describe.

What experience did the author have, for example, to link his various examples to both gatekeeping and calling people "wizards and towers with their dusty books and potions"? I imagine there's something behind that.

The risk, or challenge, is that you take your own ego-driven experiences and try to make them generic, maybe redefining a few terms along the way for convenience. Someone who has had a run-in with someone more experienced, for example, and miscalculated it as ego or gatekeeping. There's nothing wrong with that as a lived experience but of course, empathy goes both ways and that includes understanding why exactly someone may be 'gatekeeping', which is what this post seems to be about, really.