Almost all of the potential for confusion disappears if you set it so Cubase prompts you for a file location at the time of creation & you create the project in its own unique folder and immediately save it. Not too much work, maybe 30 seconds (not counting wait times for templates loading VSTi’s, etc.) - 10 of those seconds requiring actual effort on your part. Make this a habit & you won’t have problems.
And for all those projects without a name yet - I have a folder on my Project disk called ‘Unnamed Sketches’ under that are Project Folders named after the date they were created (e.g. 6-23-19) as are the Projects inside. If I decide the idea has no value I can just delete the folder. But mostly I leave them because you never know what you’ll find rummaging back. And when one of these sketches evolves into something I use Backup Project to create an entirely new Project with its own name at the top level of my Audio disk (where real songs live).
It really is not as complicated as this thread makes it seem. Yes Cubase does try and nudge you in the direction of being more organized - something most folks I know can use.