In Next, every route blows away the DOM and starts over. You can’t have nested routes like you can in React Router, where say you have different layout shells for logged out / logged in views, and then master/detail views where you navigate down a hierarchical navigation.
Well you sort of can. Just have a [view].js file, where the view variable will be the component. So you can have {view === 'details' && <Details />}
React is kinda weird… you have to do subcomponents the "React way" and I think a lot of folks struggle with that; it can feel like fighting. But I don't think Next makes that any easier or harder.
I don't know what you mean by "nested routes." Routes are just URLs that map to files. You can create a directory with files, and, uh, subdirectories with files, if you want…?