It's not clear to me whether the costs of lower specialization from having designers do a larger chunk of the work are necessarily worse than communication over

It's not clear to me whether the costs of lower specialization from having designers do a larger chunk of the work are necessarily worse than communication overhead. Having a component library is great when it'll already do everything you need it to (e.g. because in the course of your organizational history you've gone through a lot of designers and a lot of designs), but the failure mode can be a huge drain.