I own/run a co-working space which is almost entirely open plan. Many people here elect to work in this sort of environment rather than at home. People use headphones if they need to focus.

Personally, at home I am too easily distracted - I can pick through the fridge or cupboards, or read news sites forever. At the office, my screen is visible and as such I'm more likely to stay focused. I vastly prefer the incidental social interactions in an open plan office too.

Not everyone loves open-plan, but if it was truly a disaster, the space wouldn't be full.