>There's no reason that API driven design has to involve client-side rendering. You can always consume your API on the backend and render on the server.

I'll give you that I suppose, though I understand it as a lightweight server, and heavier client. On the other hand, splitting up your components into API and page-rendering servers (in addition to your database, caching, messaging servers and your reverse proxies and load-balancers) complicates your deployment and maintenance and you pay for that - so it isn't quite the panacea and now you really have to decide whether it makes sense to go down that route, that early.