This is more or less my stance - you absolutely must be capable at a game (at the very least) to review it, and there's no way around that.I think the idea that someone who is particularly inept at any given game can offer more valuable criticism than someone who properly understands it is a little laughable, and I don't think there's anything gatekeepy about that.
But Takahashi wasn't reviewing the game, and I don't think he typically reviews games at all. This video is a little dumb but I find it hard to lambast him for it. (I think that his first reaction on Twitter after the video went viral was to blame the game and say that he had no way of understanding that standing on a higher object would let him jump farther is.... not a good look, though.)
I think Dean Takahashi or the particular details is actually irrelevant to why this became such an issue. It's actually an old battle that is still being fought, hence all the invocations of "gamergate!".
Skill itself is a mechanism of "gatekeeping", it effectively creates hierarchies of players (and one would assume this hierarchy mostly overlaps with the "understanding" of the game). The question is whether videogame criticism or analysis should be aligned and valued along those hierarchies, i.e., are all opinions equal in value? The published game journalist or critics, who are under the most scrutiny, just happen to align with the belief that makes their output have to meet fewer ("elitist") standards, but ideas go a bit beyond that. The big worry is about "inclusiveness", a sort of ideal often held to be the highest goal. The need to for skill effectively weeds people out, it excludes them; to be pro-skill, is to be pro-exclusion.
If it wasn't obvious from the language here, this is all tied together to difficulty or how game mechanics (which often obtain "meaning" from difficulty) are not perceived as "artistic". If the part of games that make you fail (completely, not temporarily) is not art, then you don't need to succeed at the game to be an art critic and you don't need to (in fact, you mustn't) put failure into your game as an artist.
I'm most amused by the canards involved though. There was a facebook rant, by a game journo, which used the political winds to try to pair this incident (effectively, pro-expertise by the "gamers") with the common distrust of news media (anti-expertise), i.e., if you think someone should be good at the games they review, you are anti-expertise. Just in this thread, there is a lazy attempt to associate calling out a lack of skill with insecurity; the idea that your opponents believe what they believe because of a mental or personality defect is obviously popular, because of how convenient it is. Finally, there's the lecturing how if there is some small amount of harassment, it means you cannot take part in criticism or mockery of an individual. "Huh? You think that's clever/funny? Yeah, well, what about these bad people who agree with you? Hmmm!?" This is fairly asinine because there isn't a single important or controversial opinion you can have that isn't associated with some amount of meanness in human interaction by someone, somewhere.