Having a single, cryptographically assured source of truth for routing data is a turnkey censorship nightmare waiting to happen.

All it takes is a national military to care enough to put pressure on the database operator, legal or otherwise, and suddenly your legitimate routes are no longer accepted.

If you think this wouldn't be used to shut down things like future Snowden-style leaks or Wikileaks or The Shadow Brokers, you may not have been paying attention to the news.

> Build an industry coalition. Put pressure on those who don't join. Randomly throw away 1 out of 10000 packets from the providers that fail to get with the times. Increase that frequency according to some published time function.

What sort of incentive would anyone have to join such a coalition? Why would anyone work with providers from such a coalition, when they can work with an alternative ISP outside it and not have to deal with packet drops?

I think you're underestimating how many people have been attempting to solve this. The Internet community has some quite clever people in it, but it's also very, very large, and sweeping changes are difficult to pull off (see: IPv6 adoption).

and who should be the spearhead of this coalition?

Let's not forget that this is mainly a political problem and not a technical one. Would countries be willing to join a coalition with heavy influence from china for example? (or vice versa with the US).