In general, my argument against PyneCone is that it relies on what (from what I can tell) is an outdated Model-View-Controller (MVC) strategy for state management. Over time, frontend developers have found that MVC just doesn't scale well. Wherever possible, ReactPy tries to replicate the well-liked and battle-hardened interfaces pioneered by ReactJS.

With that said, it seems like PyneCone, as it says, comes with a few more "batteries included" - for example, a database and built-in components based on Chakra UI. This comes at the cost of some flexibility though of course.