WASM is just a bytecode format for a stack based vm. Granted it is weirdly named, the actual "Assembly" equivalent is WAT.

But the point is, it is a format specification, which has nothing to do with safety. You can implement a totally unsafe WASM runtime if you so choose. Personally I think it's not a bad thing, at least we have something like it that can run in a browser environment. But I am curious to know why you dislike it so much.