Yes. Real offices for everyone, and some open space (e.g. meeting and lunch tables) for people who want it. People should be in contact some of the time, but not exposed to every inane conversation.

Also, open-back visibility (that is, being visible from behind) does more damage than the noise itself, and there are no noise-canceling headphones for that.

Office space isn't that expensive, compared to the productivity loss of having everyone work in a crappy space. (Compared to a traditional office, open-plan saves about $300-450/month per employee in San Francisco, Class A commercial real estate. It's less if you're in Oakland, Brooklyn, or the Midwest) Open-plan is just another case of crappy HR (the norm in tech, sadly) "cutting" costs in a way that actually externalizes them; there are marginal savings on office space, but productivity plummets.