The economics of the situation aren't friendly to humans, because human intelligence doesn't scale up well. Take energy consumption-- once you're providing someone 3 square meals they can't really use any extra energy efficiently. So we try training up lots of smart people and having them work together, but that causes lots of other problems-- communication issues, office politics, etc.

Additionally you can't replicate people exactly, so even when Einstein comes along we only have him for a short while. When he passes away we regress.

Computers are completely different. We can ring them in power plants, replicate them perfectly, add new banks of CPUs, of GPUs, wire internet connections directly into them, etc.

This didn't used to matter because the old "computers can only do exactly what you tell them to do, just really fast" limitation. Now that computers are drawing, making art, modifying videos, playing Chess and Go preternaturally, playing real time strategy games well, etc we can see that that limitation doesn't really hold anymore.

At this point the economics start to really kick in. More machine learning breakthroughs + much, MUCH bigger computers over the next decades are going to be interesting.