I read Marie Kondo in one evening while preparing for my move. You know when you're at a party and you accidentally mention a topic that the other person knows way too much about, and now you're stuck in a two hour lecture? That's what reading Marie Kondo in one sitting felt like. At least it got me to throw away a bunch of stuff I otherwise wouldn't...
Digital drives are so cheap these days that there is little reason to throw much away. I keep all of my digital files from all of my university classes, for example. The only thing you need is a decent file organization or a great search tool, and I don't want to depend on the latter.
My general file system is rather straightforward: have one (solid state) drive with all the important files on it and categorize them in a way that makes the most sense for you. I advice you to separate your operating system drive from this file drive, which allows you to do clean installs whenever you want and have everything file where you left it. Plus, it makes backups super easy because I can just drag one folder to my backup drive and press 'overwrite all'.
I organize mostly by what kind of file it is, because when I look for a file, I probably know what type I'm looking for. My main folders are:
Applications (only those that benefit from being on an SSD)
Creativity (for things that I make that don't fit in a project)
Documents (subfolders based on document types, like books or notes)
Films & Series
Geodata (only the cool stuff, I use a slow HDD as a scratch disk)
Pictures (subfolders by year, then by album)
Study (subfolders by year, then by course)
Your current Temporal Locality implementation might not work, but that doesn't mean the concept is garbage. I use my Downloads folder in a similar way. Have you trudged through Getting Things Done by any chance? One of its highlights for me is the idea of an (in the book physical) In Tray, which is where documents and files and whatnot enters your system. I only keep stuff in there that is temporary or that I will put in the correct category at a later date. Once in a blue moon I clean that folder up and move stuff to the right folder. The desktop is only for files that I need right now.