Yeah I have a game journal I keep. I originally had it on twitter thinking such a huge site would never go anywhere and wouldnt have any problems. I've since moved it to Mastodon. Everytime I finish a game I writeup a brief toot on my experience and throw in some screenshots.
I started because I was burned out on games and wasn't enjoying anything I played. The journal helped motivate me to finish games so I could share my thoughts, and I found myself really enjoying the hobby. It also helped me budget my time better so I do a lot more of my other hobbies/interests as well now.
On steam I use a few categories for my library there, which are fsirly easy to set up. Finished games get uninstalled and removed from my "playing" category and put in the "done with" category.
I just have a page in the back of my diary where I list the games I've played, but I also use categories in my Steam library to organise my games into finished, in progress, unstarted and abandoned
It's not exactly a game collector site and it's kind of flooded with softcore porn and creeps, but no one bothers me doing my own thing, either. I can track movies, shows, and games there and I like how it's setup, and I can make as many lists as I want. Easy for me to add stuff, too.
You can also track books there but I use other sites for that (librarything primarily, atm.)
I've thought about making my own list-software to my specifications but that's definitely a pipe dream atm. I love making lists.