> Marvin Minsky "proved" that there was no way a perceptron-based network could do anything interesting

What result are you referring to?

Haven't read the page but a promising-looking search result is here: https://seantrott.substack.com/p/perceptrons-xor-and-the-fir...

I'm sure it's an oversimplification to blame the entire 1970s AI winter on Minsky, considering they couldn't have gotten much further than the proof-of-concept stage due to lack of hardware. But his voice was a loud, widely-respected one in academia, and it did have a negative effect on the field.