It's still kind of an open problem. There are partial solutions, but not yet really an integrated one. There is Hister: https://hister.org/ that builds some sort of drive-by index of what you're browsing anyway. And there are "true p2p" solutions like YaCy: https://yacy.net/ but it takes ages to crawl the open web (and lots of storage). There's still a lot of optimization to do in this space.