It might us a thousand years to get anywhere close? I don’t see the good arguments for all of this happening soon.
Unfortunately we could probably optimize it, a lot.
All I have to say is that in 1900 many thought flights by heavier than aur craft were tens of thousands of years away. 3 years later it was achieved.
Predicting the future is hard. Some problems are harder than expected, others are easier than expected. But generally I'd say history favors the pessimists, the cases where a problem gets solved suddenly and there's a major breakthrough get a lot of press and attention, but they're a minority in the overall story of technological progress. They're also unpredictable black swan events - someone might crack AGI or a unified theory of physics tomorrow, or it might not happen for ten thousand years, or ever.
Look, we can make assumptions given a much simpler technology, and the outcomes of our past selves. But, while the physics for those wings was pretty much good enough at the time, the aforementioned scientific areas aren't. And we know it.
Much of your "intelligence" is a function of natural selection. This is billions of years X bajillions of creatures in parallel, each processing tons of data at a crazy fast sampling rate in an insanely large/expensive environment (the real world). Humanity's algorithm is evolution moreso than the brain. Humans learn for a little while, start unlearning, and then die — which is an important inner for loop in the overall learning process.
Taken together, there is some evidence to suggest that superhuman intelligence must require megawatt-sized compute cluster and all the data on the internet (and a lot... LOT more)
That isn't strong evidence of what would be required by a well engineered system with none of those constraints.
Intelligence is not the end of goal of evolution, it is a by product.
The only reason why currently it takes far, far more computing power is that we have no idea how to build effective intelligence, and we're taking lots of brute force shortcuts because we don't really understand how the emergent capabilities emerge as we just throw a bunch of matrix multiplication at huge data and hope for the best. Now if some artificial agent becomes powerful enough to understand how it works and is capable of improving that (and that's a BIG "if", I'm not saying that it's certain or even likely, but I am asserting that it's possible) then we have to assume that it might be capable of doing superhuman intelligence with a quite modest compute budget - e.g. something that can be rented on the cloud with a million dollars (for example, by getting a donation from a "benefactor" or getting some crypto through a single ransomware extortion case), which is certainly below the level which would draw attention. Perhaps it's unlikely, but it is plausible, and that is dangerous enough to be a risk worth considering even if it's unlikely.