I can assure you that more people exist with B1 knowledge of english then folks that have at least minimum knowledge of all math and computer science related do

I can assure you that more people exist with B1 knowledge of english then folks that have at least minimum knowledge of all math and computer science related domains that are used for deep learning (even subset like audio/video) even if we use only using software engineers/ml engineers as reference you have so much domain knowledge needed to even consider reading notation (without proper explanation in docs). And most of the variables in code still will be in english or other natural language so it is just easier to read english then read math notation mixed with english/other language for MOST (not all) people using underlying software.