Not at all. Rather you might want a tight coupling because it will allow you to integrate deeper. Having the same code running on client and server when your a

Not at all. Rather you might want a tight coupling because it will allow you to integrate deeper. Having the same code running on client and server when your application is split between running both on client and server is very convenient. As an example, a React application with server rendering and then progressive enhancements on the client. Very common pattern.