This is infrastructure is poor in some places, some areas have failing infrastructure (such as flint MI)
These types of projects require an elected official to see beyond their term limits. Something few of them can do.
i.e. see beyond the need to focus on short-term sugar highs for voters, to get re-elected every 2/4/6 years.
Politicians think short-term for the same reason public CEOs so often do: near-term placating to retain their position.
I can relatively easily block Facebook if I want to, on every site I visit. Try figuring out a way to eliminate all of the NSA's data hoovering of you. Tell the TSA you're not giving them your device, etc.
The Cloud Act is government legislation, that was not initially promoted by private industry. Private industry gave in over time because the alternative the government would pursue instead is far scarier. It was a compromise to keep the politicians in DC from doing something even more draconian. I don't agree with that compromise, however, just try saying no to them (see the Yahoo fines).
The internet already functions well enough for purposes of decentralization. Sure, there are some clear improvements and some less clear trade-offs that could be made, but the brass tacks is that these are social issues, not technical ones. They have to be addressed at the social level.
There has been some shadowy coordinated push behind the scenes over the last week, corresponding with the CLOUD Act and other dubious events, as described above. I believe this is just the beginning of such coordinated pushes. There are powerful forces at work looking to assert their authority and control over the open diaspora of the internet.
Americans take free speech for granted, but they forget that open forums where anyone can make a strong argument that lives and dies on its own merit are extremely dicey for the status quo power structure.
My belief is that the 2016 election pushed some fence-sitters over into the belief that the internet as constituted is a threat to their power, and that they are working triple-time to fix the situation. Ultimately, I believe this will evolve into something like a government verification and ID check system before someone is allowed to publish, and a YouTube-like strike system that will take away those rights as people are "abusive" or otherwise express wrongthink.
The relatively-free internet of the 90s and 00s will be driven into the darkweb where anyone interested in accessing non-corporate-approved content can be trivially mischaracterized as "a Russian agent or sympathizer" (if not much, much worse). What just happened with the purge on reddit is part of that.
The internet has been re-AOLized over the last several years as massive tech companies have consolidated against the grassroots nature of the homegrown internet. The CFAA and the Copyright Act allow companies to sue the living crap out of anyone who tries to free user data, and Google et al now have the resources to enforce this thoroughly.
The long and short of it is that a new network or protocol may offer some nice features, but it's not going to solve the key problem that ensures maintaining a free marketplace for ideas will always be hard: the rich and powerful don't like things that may threaten said richness and power. The internet is arguably the most powerful such tool invented since the printing press.
As another commenter expressed above, the real question is why this has taken them so long.
Less charitable: they already made their money and are fine with pulling up the ladder.