I'm reading HN regularly and didn't see similar discussions. You are right, I should have searched for it before submitting. There's no need to be toxic though, I was genuinely curious.
Sorry, I did not mean to be toxic. But I really believe that anyone complaining about math notation should try to propose something and show us a page or two to judge. I would also appreciate some examples showing possible improvements in notation. I don't understand what's wrong with Sigma, I find this notation beautiful, as well as integration sign.
Math is still taught at the blackboard and the notation works fine there. See for example https://www.youtube.com/c/FredericSchuller - he is very careful to explain all notation he uses and he is writting down more text than the usual professor. In my opinion it shows that math notation is fine and the problem is that ideas behind are complex and hard to grasp.