I think this may not be the easiest path (at least short-term) but I would be Apple I would only actively maintain my own JS engine but I would also try to make

I think this may not be the easiest path (at least short-term) but I would be Apple I would only actively maintain my own JS engine but I would also try to make a nice abstraction for others JS engines, i.e. what Google chose not to do. Maybe it wouldn't be ideal for short term performances, but community wise and future wise it would be a great choice I think. Sadly I don't think this is the path Apple is going to take.