A double spend attack is a type of fraud for sure, but obviously one of the remedies for a double spend attack is to fork the main chain and change the consensus to nerf the attack.

Ultimately layer 0 of a blockchain is the community that uses it, and if they decide to fork en masse, they will do so. It's an essential property of the system itself. Blockchains would not be antifragile if they could not fork.

Then the problem becomes the same, who is empowered with calling a fork? If they are just by users who are using it, how is it different than having an election etc.? Except here the agenda comes from a shadow organization within a "decentralized" system. I would much rather my votes happen in public with everyone's consent.

I don't see how double spending and forks are the same thing. Double spending is when the same coin is spent twice on the same chain. When you fork, you are creating a whole new future history (sorry, can't come up with a better word). If I have a ledger for my business, and someone created a copy and added different transactions to it, that would not be double spending, right?