There have been studies going back as far as Peopleware and The Timeless Way of Building that suggest people are generally adversely affected when the noise is more than noise they personally generate (e.g. keyboard clicking), and not in their control (e.g. choosing to listen to music may be fine, but when you’re forced to listen to music because the alternative is a distracting conversation between teammates it has adverse effects).

The other thing, especially mentioned in The Timeless Way of Building, is that you need privacy to reach a state of flow. It doesn’t necessarily mean you’re isolated or that no one can interrupt you, but it means nothing in your immediate vicinity is triggering your peripheral vision or any sense of a fight vs flight reflex because someone’s walking around right behind you, etc. Most of that research advocates that individuals should be allowed to customize these aspects of their personal space, like privacy, quiet, lighting, ergonomics..

More generally though, it’s not about what works for you or for me. It’s about what we can empirically learn about states of flow, and on that front it’s utterly beyond dispute that open-plan offices are disastrously bad.