It seems that by "expected", you mean "expected, by anyone who read the spec" which I don't think is a fair use of that word. Obviously, most JS developers have not and will not read the spec.

I am very happy with JS and TS and I think the coercion rules are easily worked around with linter rules and policies, but they are definitely weird and I think the language would be better if it simply threw exceptions instead. But then, such an issue shoud not be surprising for a language that was designed in 10 days.