Or put another way, governments would chose to intervene by helping to create more 'competition' - which creates product variations approximating true market needs - as opposed to trying to 'legislate features'. 'Feature lists today' but something else tommorow. If the market is healthy, it will move in the direction of value, is the idea.
Governments can also help by promoting and supporting standards.
A famous example, Yahoo!, didn't walk away from search and partner with Microsoft because of the difficulty of building an index. They did it because it was going to cost billions per year to try to keep up with Google in producing results.
I'm not arguing there's no work to do in building an index, but the problems of crawling and indexing can be solved by cash. They're a moat against small challengers, but not against well capitalized ones. Ranking and filtering require lots of research and tuning. This is the moat against even the well capitalized.
Put another way: do you really disagree that Google would still easily dominate search based on result quality even if small startups got access to their index data?
There should be multiple rankers on top of the index, users should be able to choose and create new rankers. Same for filtering - what gets hidden/censured, put the power back to the users, let them select their filter lists. Instead of one true ranking and filtering, let users customise it as they like.