Found this video really interesting as I have a relatively large backlog myself. Fortunately not nearly as large as this one.
Personally, I’ve only ever considered games I own to be part of my backlog, which makes my list much more manageable. That said, I have a large number of unplayed games on both Steam and GoG. So to start I’ve decided to play all my GoG games first (as that is still within reach). I’ve promised myself not to buy any more games untill all my GoG games are either completed or marked “did not finish” due to it not being my thing.
Whenever I hear of a game I might like, or buy one on a whim I add it to a list. I do something similar with books and movies. The purpose of the lists aren’t to put pressure on myself, but to remind myself of all the things I’m interested in and to avoid the feeling of “I have nothing to play/read/watch”. If I’m not enjoying something, I just won’t finish it and I check it off the list so I know I tried. For me, deciding what to do with my limited time can give me analysis paralysis. I don’t see the list and backlog as a chore, but more of an easy menu of options that I’ve already considered.