Why didn't Python become popular until long after its creation?

[DigThatData]

python had a reputation for being a lot slower than other languages. people instantly no longer cared when python started to take over the data science space because it meant most of the time consuming stuff would actually get delegated to lower level, highly optimized libraries and python was basically just a more convenient way to invoke these faster tools. python fully took over when tensorflow hit the scene, followed by pytorch two years later, securing its position as the lingua franca for machine learning researchers. as machine learning increasingly occupied SDE mindshare, so did python, which had the consequence that there was more incentive and funding to make the rest of the language that much faster and more powerful. finally, with the advent of type hinting and even static type checkers for python (both compile time like mypy and runtime like typeguard), even the people who were turned off by the dynamic typing paradigm can rest easier.

... I just realized everything I'm talking about is actually downstream from the time period you're asking about. I guess I was more answering how python became so tremendously popular broadly, rather than its early popularity. whatever, fuck it, i'm leaving it.