There’s a pattern I’ve seen in a lot of class components that doesn’t fit as well in a functional component: every time the component needs to render some new bit of JSX, create renderThing(), renderOtherThing(), etc, ad infinitum. These just don’t happen in functional components. Technically, you could create an inner function, but people just don’t seem to do it as much. They create a new component. Or at least, in my team, the resistance to breaking that stuff out to separate small components was much lower than with class components. It took very little effort in code reviews to push people towards small components and do it consistently.