That is a very interesting project indeed, but it’s somewhat orthogonal to this, and that approach is a lot more experimental. Basically, for this VM I’m pretty sure we can get it work how we want it to work, and there are very few truly open questions as to its feasibility**, while risc0 has a lot more of those. I wouldn’t be surprised if a “traditional” VM like this would would be better for certain types of computations, and a ZK-style VM would be better for different types of computations. Maybe eventually we’ll end up using both? I don’t know.
Anyway, you might want to take a look at this thread where Sergei’s currently experimenting with risc0: Trustless wasm compilation with SNARKS?
** – essentially the only major open questions are, I think, 1) how much faster can we actually make it than it already is, and 2) how much more accurate can we make the gas metering. The rest is mostly just getting the engineering right.