>>andsoi+OMb
The why: because Lua, Python, JavaScript, Janet, etc lack many or all these features. And each of these features is known to make life easier for a human programmer.
>>nine_k+gRb
Looking through that list of features, Ruby (the dynamic language I know best) has all but 1 built-in (and the other can be added with Gems). I'm guessing Python probably has them all too (but I don't know Python that well). They're pretty common. So the why still isn't clear.