Contrast that with cryptocurrency where a bunch of VC money pumped up a market for you to launder the proceeds and the protocols are intentionally designed not to have antifraud protections. Ransomware was possible a decade earlier but the profitability went up massively once it became easy to launder millions rather than hundreds of dollars.
This explains reliable, stealthy, zero-interaction full-chain iOS vulnerabilities, which fit into every intelligence, military, and law enforcement business process pin-compatibly. It explains browser vulnerabilities and ATO vectors.
And it also approximates the market for blockchain vulnerabilities: if the exploit is "literally transfer untraceable cash from victims to buyer", lots and lots of criminal organizations already have that business process; you probably simplify their existing repeatable process.
Blockchain vulnerabilities thus have a very credible market. As bonus: the work of discovering and POC'ing these vulnerabilities may be gnarly, but the engineering required to exploit them at scale probably isn't. It doesn't take months of R&D to make the exploit "reliable", it generates straight cash until it dies (and probably has a half-life measured in minutes), and so on.
Every lucrative class of vulnerability has some kind of story like this; they all fit into some existing, very clearly stated demand.
We get into trouble trying to generalize. All the markets are very specific; they're all sui generis. Most vulnerabilities are worth zero. There are mobile OS RCEs that are probably worth zero!
Jacking a database and trying to sell it on a DLS or dark web is a massive process.