From a naive perspective such as my own, the concept of a “Single Page App” having multiple pages seems like an oxymoron. Is SPA less about defining the structure of an application in a single interactive view and more about defining it as loaded from the backend as a whole application at once even if the frontend organizes things in multiple views/pages?
In the olden days navigation on a website caused a full round trip to the server which responded with the whole HTML page. The promise of SPAs is that the client once it’s running only needs to fetch necessary data in whatever format it likes - which can actually be more of the client code loaded lazily - without a full page reload thus maintaining the current state of the app.