This is admittedly secondhand knowledge, but my understanding is that the EVM was written with 128 bit words, and consequently cannot be implemented using any common general purpose computer hardware. All of its operations have to be implemented in software, making it significantly slower than it could be as a result.

Isn't the whole point making the decentralized network itself the computer...?

Market makers need the ability to process transactions quickly. There is indeed a network of computers involved, but each computer is, well, a computer, and needs to make computations in order for transactions to process.

Does a zkEVM by Loopring+Vitalik consulting on it scratch your itch?