More importantly there are lots of possibilities for disaster caused by the lack of typing, and complex Mathematica code quickly becomes impenetrable. Oh and version control systems are all but useless for the main ".nb" file format. Again, just like Excel.
You try it once, realize it's doing things element-wise, and then go lookup the proper product symbol (@ in numpy).
I don't know the motivation of the decision, but "ElementwiseProduct" is harder to type, and still has a lot of use cases.
I mean footguns in "Multiplication with multi-dimensional arrays"? That's a problem with Mathematica as opposed to what? Implementing it yourself? Using a third party library for that (that you have to also find and assess it's doing the right thing - which apparently numpy also doesn't as you say). Another specialized tool (and wouldn't that just have it's own footguns)?
If you just said "it has its set of caveats that you need to be careful about" that would be understandable.
But your wording/tone implies that Mathematica is somehow worse, and using it is (your words) "a terrible idea". So, what are those wonderful alternatives that don't have the same and much worse issues?
Neither of you have to be wrong, but insisting that Wolfram isn't liable for the situation isn't right. They built the moat, now they have to deal with people falling in on both sides.