If requesting any set of random words or characters in the path part of the URL always returns a page of content and 200 OK status then you have infinite URL space. I'd call spam on this too.
A website should have a finite number of URLs that will return 200 OK status and some content. Others will return 404 or 410, and certain formats will 301 redirect to the canonical URL for the content. If anything and everything returns content with 200 OK status, that is not a good signal.