But it wasn't just "open competition." Many actions of the centralized de-facto internet monopolies of today (Facebook, Google, etc) were—and continue to be—horribly anticompetitive.
Furthermore, just like in the offline world, "open competition" doesn't consider externalities, like the loss of privacy, and the massive social and political influence that these behemoths have gained.
Now a crowd of people are suggesting something very different: that people wouldn't care about giving up the conveniences of today's centralized systems. But we do have experience with a less centralized web, and it wasn't a lack of "web3" tech that resulted in the centralized systems gaining their current position. It was open competition with the less-centralized old status quo. The centralized systems that won are very different than the older centralized systems that had lost - AOL tried to force everything inside of its wall; Facebook and Twitter merely extend their reach so that they can touch everything, and won out as aggregators vs doing in-house content production.
So why would the desire to have such convenient, one-stop-shop, minimal-setup centralized aggregator services go away?