Y'all are trying to make fun of this, but it's really a brilliant tactical move. Think about it; Musk desperately needs to flip Twitter, and this branding change both makes the site much more attractive for a potential buyout from a porn company, and also lowers the valuation of Twitter even further to the point where it's probably within range for a decently sized porn company to buy.
For HN in particular I feel I need to clarify this more often[0] -- but this comment is a joke.
It's riffing on the idea that Elon thinks "X" sounds cool but it actually just sounds like a porn site, that the valuation of Twitter would need to drop substantially for a porn site to be able to buy it (and that this rebrand is likely to further devalue Twitter), and that it would still be a terrible waste of money for Elon even if the fictional "plan" succeeded because he'd be selling at a substantial loss -- but in the context of the joke, it's implied that Elon wouldn't see it that way, he'd see it as a success.
It's meant to satirize Elon's plans for Twitter (and common defenses of Elon's mistakes that show up on HN) by implying that the downsides of "X" are so obvious that Elon would need to be aware of them and would need to be incorporating them into his "plan"; but even so he'd still be the type of person who would make a plan with obvious downsides (ie, selling his company off at a substantially lower price than he bought it for) and just not realize that those downsides exist. The joke frames itself as if it's going to be a defense of the rebrand, but then just goes on to describe an outcome that would be terrible for Elon anyway.
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The actual non-joke reality is likely pretty much exactly what you say -- Elon has owned "x.com" for ages and has always wanted to name something "x.com" and he has a grand vision of an everything "brand" that probably mostly just seems cool to him and that he's convinced would seem cool to everyone else as well. But he's unable to see that to everyone else it just looks like he's rebranding into a porn site.
He's convinced himself that this is a master plan that could lead to his Everything App dominating the Internet. But to everyone else outside of his bubble, the downsides are obvious and the plan just looks silly.
And thanks for the book recommendation, I'll add it to my list :)
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[0]: This is not a criticism of HN, I am myself much more prone to missing jokes than the average person and I regularly rely on context clues to figure out if someone online is joking -- and those context clues are usually missing from HN. So very much no shame to anyone for not catching a joke, I get the confusion and I also regularly miss the exact same jokes.
Gotcha. I guess I misunderstood. Thanks for the clarification.
As an aside, I tend to only like the joke that Elon Musk is Phony Stark, the rest of the jokes just don't land with me for some reason. I've never really liked the guy and I'm happy it's a lot less difficult for me to articulate why now.
Mass migration is definitely a concern for potential buyers, but it's fixable. A porn company might be able to slow current Twitter migrations down by implementing smart policies like not rate-limiting their own app.
Also keep in mind the opportunities to regain advertiser trust by pivoting the content focus; many advertisers may prefer having their products shown next to pornography instead of nazis.
