The problem with that is privacy and security. Any machine you trust with the computation can both see the data and can compute dishonestly, unless you use (ext

The problem with that is privacy and security. Any machine you trust with the computation can both see the data and can compute dishonestly, unless you use (extremely!) expensive forms of encryption and verification. It's not micropayments holding back decentralized compute, it's that fact that you are dealing with untrusted counterparties.