FAI seems to me to be mostly about serial depth of research. UFAI seems to be mostly about cumulative parallel volume of research. Things that affect this are effectual even if Moore's Law is constant.

I wonder how much of this estimate is your distance to the topic; it seems like there could be a bias to think that one's work is more serial than it actually is, and other's work more parallelizable.

(Apply reversal test: what would I expect to see if the reverse were true? Well, a thought experiment: would you prefer two of you working for six months (either on the same project together, or different projects) and then nothing for six months, or one of you working for a year? The first makes more sense in parallel fields, the second more sense in serial fields. If you imagined that instead of yourself, it was someone in another field, what would you think would be better for them? What's different?)