Why 2018?
There is no "internet," it's just some propaganda outlets attached to the surveillance devices you have to keep in your home to participate in the economy. It is no longer a popular elsewhere, 2018 marked the inflection point or epoch of the internet becoming just another homogenized organ of the leviathan, not to connect people, but to atomize them, imo. It is a walled garden that is completely surveiled.
I'd speculate that the majority of people who use the internet now are young enough to have almost never lived without it, and it forms the substrate of their ontology, instead of being just a thing that is separate from real life. They have no sense of it being an objective fantasy realm.
Why does it matter whether he has shackled himself to one side of a political binary, or cares for the happenings of a singular website and its owner?
As for moderation, I believe they were lamenting the corporatization of the Internet and how it has become a hotbed for controlling the populace, rather than connecting the populace. Which would presumably fall under a preference for unmoderated communication.
As such, the same US left now saying that one shouldn't take those Twitter files seriously is quite disingenuous, if anything, the Twitter files seem more real than any of that Trump-Russia fiasco.
I propose, for example, "equating abortion to murder", "misgendering someone", "calling someone the f-word", "saying that f-words are molesters", etc.
Most of the big platforms (such as Twitter or Meta) are just in the middle. Twitter before Musk moved one point to the left, making misgenderisation a bannable offence, but I think Musk undid that. As a data point I have had comments flagged for doing the first one here, so you can tell where this community stands.
I have absolutely no faith in changes made by Musk, but I have to say I still remember the days when the platforms, instead of silencing everybody by default, trusted you to make a judicious use of the block button, like a grown-up would.
It all culminated in the summer or 2020 (for the Anglo- and Anglo-influenced world, at least), but, hopefully, I'd say that right now we're in the middle of a vibe shift. Evidence number one is the launch of Threads itself, which feels like the launch of a dead carcass out in the sea.
All this to say that the OP is correct, social media is dead.