But the CPU would be thoroughly confused in many cases. Like if you added a number with a string. This means low level tools have too and therefore people who do low level programming are confused and the generally carefree has rules can make it difficult to debug js.
Also I think rust making you write "safe" code unless you explicitly tell it otherwise is a great thing.
So I think that tools telling the user that they're doing something wrong is great, tools telling the user to stick with physical limitations for better performance are completely valid but what js does seem really weird with having constants be reassignable, making them nothing but labels combined with HTML I find it even more annoying.