Yeah, Next.js defines the routes using the file system. So folders are how you define a route segment and the page.tsx or the route.ts file inside that folder is what make the route actually get created. So if you want to have a route you need to have a folder.

https://nextjs.org/docs/app/getting-started/project-structure#nested-routes

Also it's pretty common to have the folder structure you have mentioned. /account/signup will be rendering the signup form and /account/login will be rendering a login form.

If you don't want the /account page to render anything you can omit the page.tsx file for it. So it won't be created as a route.

Thanks for confirming that. Removing the page.tsx of the account route shows a 404 page with my root layout. Is this by design and do you think I should redirect if someone tries to navigate to /account?

Yeah, for any non existing route Next.js will show a default not found page. You can create your own by adding either a global-not-found.tsx or a not-found.tsx for any route.
https://nextjs.org/docs/app/api-reference/file-conventions/not-found

Or you can redirect the user if you like.

not familiar with global not found

Ah its new, but why would anybody use it? I can see why theres a global error but global 404 makes no sense to me

404 is a not found error so if you have accounts dir and no page.tsx or route.tsx then there's no route to be found.

You can either add a page or route file to that directory to handle what you want to do when the route is hit or you can have your own custom not found page which can be displayed. You can do this globally for the entire app or locally for each route inside of the folder

Having a custom global not found page shows the custom page for every 404 on your application