>How many did say this?

I don't know about chess, though earlier computers didn't have the power, so people could've reasonably said that.

But we certainly saw it with Go. Many people said that a computer could beat a person at chess or checkers, because they were simple, limited games, but Go was too complicated, too many possible combinations. A computer could never beat a Go champion. And here we are, with multiple generations of AlphaGo pushing the boundaries. They might use a couple thousand CPUs and a few hundred GPUs, but they can do the impossible thing.