Required energy density at the necessary scale will be your next hurdle.

Once you have the efficient algorithm you approximate asymptotically with the energy you have, of course you can’t obtain the same precision

Or speed. I think Frank Herbert was on to something in Dune. The energy efficiency of the human brain is hard to beat. Perhaps we should invest in discovering "spice." I think it might be more worthwhile.

Okay, enough eggnog and posting.