Do you mean the increased productivity will be the competitive advantage, or they'll have a recruitment advantage to be able to attract candidates with a comfortable work space so they're not stuck at home? As a hypothetical candidate in my next job search whenever that is, I'll definitely be wanting the latter.
Personally I suspect early-stage companies, and companies working on "hard" technical problems that require more collaboration and abstract thinking will have an advantage by working in person. But who knows! Maybe a silver lining of the pandemic is that we'll finally get some usable data on the effects of remote work and remote culture.
