People vastly underestimate how complex client side code can get and how much automatic functionality browsers hand you. Whereas a nice web framework has users, permissions, session management, templating, validations and forms all set up for you with battle tested out of the box behaviors.

A frontend framework is great if you are a company that really needs to slim down bandwidth and can hire expensive devs to maintain it. But for a simple no nonsense business application it’ll just slow you down and will gravitate towards being a mess.