You can't remove JavaScript features without breaking websites. The one exception was when the strict mode pragma was added, but that was a one-off, and there's

You can't remove JavaScript features without breaking websites. The one exception was when the strict mode pragma was added, but that was a one-off, and there's too much resistance now to add more pragmas (they tried that with "strong mode"). The best solution currently is to have linter rules enforcing ===.