It’s a good point. UI is a situation where the classic OOP-style frameworks work really well when they’re carefully designed. I think we’re still waiting on a model for doing that with FP that doesn’t rely on passing state deep down into an expression tree like React and its descendants encourage you to do. There’s stuff like Redux but it has its own problems.
I should've clarified. I meant developing a web page to run on a web browser, hence the form example.