How long until it’s computationally feasible to use things like MPC/FHE for uses as complicated as OFAs/decentralized block building?

What are the major performance improvement hurdles from here to there?

Running first twitter vs farcaster simulpost test where the smart ppl at

I feel like there's lack of motivation for implementing protocols like those, only a handful of people are actually working on implementations.
I see a lot of research out there though, especially FHE and threshold decryption are favourites

Mostly because people don't want to deal with the math that comes with it?