Yes, this could become a problem because very often , teams change their structure, split or merge. And so do BFFs. That's why BFFs should not follow managerial politics.

GraphQL is also a good alternative. Maybe I should write an article on it too. :)

I don't know, but I find it very useful to prevent frontend devs from doing any kind of "security" in the client. This is the real enemy: frontend devs doing anything outside of the usual views, view models, local state.