If social media platforms all provided the same service, there would be only one. The way it is today, each of them makes a very specific set of editorial decisions, which is why we have Facebook, Twitter, LinkedIn, Gab, etc. If every network put all the power in the users' hands, the dynamics of network effects would take over and we would be left with one social network.
I'm not saying this would be worse for the users, because I agree that "allow all content + powerful filtering tools" would suit me just fine. But it's worth noting that there would be a real serious monopoly problem if there were no conscious choices to differentiate. This would conflict with your main point of friction here: that a bunch of SV nerds shouldn't get to define our Overton window. If one platform provided free speech + filters, and became the only game in town, it wouldn't be long before we were back in the situation we're in today, except the group of toxic SV billionaires running the show would be even smaller.
I'm not saying this would be worse for the users, because I agree that "allow all content + powerful filtering tools" would suit me just fine. But it's worth noting that there would be a real serious monopoly problem if there were no conscious choices to differentiate. This would conflict with your main point of friction here: that a bunch of SV nerds shouldn't get to define our Overton window. If one platform provided free speech + filters, and became the only game in town, it wouldn't be long before we were back in the situation we're in today, except the group of toxic SV billionaires running the show would be even smaller.