Web 2.0 spent the last 15 years taking over the internet. They made publishing easy enough for your mom. The web evolved from a niche many-to-many medium into a really global, many-to-many medium.
But... In exchange for these great, free publishing tools... most online content got concentrated and funnelled through a handful of companies. Being startups, they had reasonably diverse personas. Family friendly Facebook, anarcho-lunatic Reddit, neckbeard news.yc and pansexual tumblr...
As valuations grew, online advertising exploded and startups aged... they all end up with the same corporate persona.
I care about freedom too. But, I think a lot of liberals/libertarians (like me, this isn't shade) get too caught up in philosopmhical "blackboard freedom" and don't look at actual freedom.
An web where most content is reviewed by a taboo filter (this is what nsfw means, taboo) is not as free as one that isn't.
I'll throw out a reminder that many of the web's first communities existed to discuss taboo topics: drugs, sex, etc.
These were, for example, in my opinion, responsible for the cultural liberalisation that enabled "the great coming out" of gay and other marginalized culture.