I'll give a different answer, which is that a blockchain-based prediction market can be used as an oracle for other blockchain-based contracts. So there can be both a final answer and a mark to market for the contract which should approximate reality in some way. However, being unregulated, there's always the possibility of cornering the prediction market and causing the derivative contracts to end with unreality. So you may need another kind of oracle to finalize the market price of the prediction market.

Probably could be accomplished without crypto, but it can also be accomplished on some blockchains with minimal additional investment.

Good question. Prediction markets [1] allow people to bet on outcomes and benefit financially if they are correct.

However, many jurisdictions ban them outright claiming that they a form of gambling and challenging the unregulated nature of questions leading to misaligned incentives (“When will that building burn down?”).

Yet despite these issues, the scheme can offer a neutral ground for betting against overhyped technologies or registering dissent against the policies of authoritarian regimes.

Cryptocurrency based prediction markets further protect the participants by masking or hiding their identities.

The combination of these features makes prediction markets an effective way to deliver global-scale censorship-resistant voting to the masses.

[1] https://en.m.wikipedia.org/wiki/Prediction_market

So all you're saying is that cryptocurrencies can be deployed to facilitate illegal behavior. We've known that for quite a while.

To interpret a tool like prediction markets as you have, is it fair to say that you strongly believe in the divine right of kings?

I never said that prediction markets should be illegal -- I'm just acknowledging what you stated, that in some jurisdictions, they are. That's a fact. Running a cryptocurrency-based prediction market doesn't make it less illegal.

Your argument isn't with me, it's with whoever decided a prediction market should be illegal. Go change that person's mind.

Neutral ground is useless if the blockchain doesn't have an oracle to know what happens in the real world.

The blockchain only knows about things on the blockchain itself. So someone has to do the actual data entry into the blockchain, and that person is the weakest link in any 'prediction' scheme.