Earlier quoted context omitted.
Why would a croudsoursing site know that? This is the kind of question where 1 expert will fare better than the average of 90% of the people.
Sure. If that 1 expert bothered to post a falsifiable prediction like “x% likely this’ll happen by year y”, the rest of us could read their argument and update our predictions. Unfortunately that’s pretty uncommon so everyone has to go by base rates (crypto algorithms seem to last x years historically) and vague guesses (quantum computer capabilities seem to be doubling every x years so I dunno maybe enough qbits by…
Ok, let's get a try from a mildly informed person, that is also probably better than the 90% average...
The number of qbits seems to be growing linearly, at about 7 qbits every 2 years. Extending that trend says that none of us will ever see a quantum computer break 256-bits ECC.
But I really doubt the trend will hold. Quantum computing seems prone to surprise gains, and those are unpredictable by their nature.
About this:
> crypto algorithms seem to last x years historically
I don't think we have enough data to decide on an average, but the distribution does surely look fat-tailed, so any statistic summary you make from it will be useless.
If history tells anything, it is that algorithms that have minor attacks will be broken quickly, and algorithms that don't have minor attacks will survive for very long.