Fwiw we have at least some reason to hope in this general context that between clever systems work and tightening theoretical bounds via additional assumptions and clever reasoning we might get to practical implementations for some applications.
As (maybe weak) evidence the progress on practical implementations of PCPs/SNARGs
It’s much much faster now, and performance is improving 10x every couple of year. With the current trend, FHE will be applicable to 80% of usecases by 2025
rhindi|3 years ago