I'm in the camp of f = ui(state), and the reason for this is the extreme of streaming games where UI = frame buffer. I'm inventing my own framework for radically simplifying traditional Web apps via RxHTML which works great for crud apps. However, games requires more insight into state machines and what-not.

In terms of the logic, I wrote an entire platform to simplify multi-player board games which I'm evolving to tackle various businesses. https://www.adama-platform.com/