It's basically that. Example:

    hello.then(a => return op1(a)).then(b => return op2(b)).then(c => console.log(c);

    const a = await hello();
    const b = await op1(a);
    const c = await op2(b);
    console.log(c)

In Haskell (>>= is pronounced "bind", \a -> is like a => in JS):

    hello >>= (\a -> op1 a >>= (\b -> op2 b >>= (\c -> show c)))

    do {
        a <- hello;
        b <- op1 a;
        c <- op2 b;
        show c
    }

There is a slight difference, in that JS promises aren't monads. But the idea is still here.

what do you mean by banned? You got it the other way around, async is a special case of the do notation, and await is the special case of <-

do { a <- m; return r }

Ia desugared to m >>= (\a -> return r)

Think of it m.then(function (a) return r)