>It seems like the existing onion addressing and network handling already works to this advantage except that it relies on the fact that no two names will ever collide.
If onion names are secure, collision should be cryptographically hard to achieve. In other words, if you can create collisions they are broken in the first place and should be ditched all together.
>In which case why not allow people to register collisions then use existing onion network measurement tools to determine the popularity of sites, returning them in the same way a search bar returns autosuggestions.
Because that entails all kinds of implementation problems plus security and privacy issues.
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