Callback hell was never about promises, but callbacks (!) which would require a third-party library or some gymnastics to implement control flow. Promises and async/await both solve it reasonably well. The problem presented can be rewritten as:

    Promise.all([
        doA().then(a => doC(a).then(c => [a, c])),
        doB().then(b => doD(b), b_; return b; })
    ]).then(([a, c], b) => doE(c, a, b))

No need for `new Promise(resolve => ...)`. Or with async/await:

    const [a, b] = Promise.all([doA(), doB()])
    doD(b)
    const c = await doC(a)
    doE(c, a, b)

Is it worth introducing the complexity of visual programming to solve this 'problem'? I have a much harder time understanding the graph than the code.