Python2 was poised to take over the world and be the next Java. 3 is losing ground to Node, Go, Rust, even Lua. 3 is a really fun and productive language to work in as long as you don't need to think about bytes.

My guess is Python wouldn't have done much better anyway. The GIL and lack of client side support kept it out of a lot of use cases.

Really? I’ve been using Python for 15 years and never heard anyone say “GIL”. How and what is GIL preventing?

It causes issues with running low overhead multithreaded code. I get by with the multiprocessing library, but then again I don't have a lot of threads (10 is the most I've ever needed), some people want to run hundreds of "light threads" depending on the type of programming that you are looking to do.

Statistics and probability.