The "Cumulative distribution of predicted Years to AI, in early and late predictions" chart is interesting... it looks like expert forecasts regarding how many years left until AI have hardly budged in ~15 years.

If we consider AI to be among the reference class of software projects, it's worth noting that software projects are famously difficult to forecast development timelines for and are famous for taking much longer than expected. And that's when there isn't even new math, algorithms, etc. to invent.