Except that all of the studies suggest the headphones / earplugs option doesn't help very much. Most of the damage is done because of lack of privacy and noise is a secondary (though still large) effect.

The headphone solution is also insensitive to people with extreme aversions to distracting sounds, such as sufferers of misophonia. In a lot of cases, if you are embedded in an open plan, there is no such thing as "opting out." It's a fixed decision mandated upon you.

headphones don't let you opt out of an open office. there is still noise you can hear above the music, visual distractions, proximity, catching colds, 6 person meetings on neighbours desk, everyone cans see your screen etc.

Headphones are a shitty solution, and laptops make it easier to opt into whichever you want.

Opt out = permanently damage hearing?

everybody's jiggling! argh!