I do think that the people who are buying older games as they're cheap are smart. I mean, I know I could, but won't. I like to stay more into modern gaming because I know I'll miss out on a lot of indie games at this point which are going to increase in price due to their limited print releases. I know I'll be paying more but I'll eventually go back to older consoles once everything goes all digital and at that point I'm pretty certain prices will increase drastically.
Considering your PS5 is digital only I wouldn't even bother, but I myself refuse to do digital so there is that.
When it comes to modern gaming, I think the combination of AAA, AA, and indie make for some great games, but when it comes to AAA alone, I think half at the very least are trash. It's like AAA developers feel the need to make everything open world and when it comes to most modern open world games, my experience with these games is just overall disappointing. The latest open world game I've played is Ghost of Tsushima, one that is very widely praised, but instead the game is like a poor man's Nioh with an open world, taking just so much time getting to point to point and the game just feels so much like every other western action game that tries to add depth. It just so completely underwhelming.
It's not like you can even see how good or bad an open world game will be because not all of them are bad. But either you're willing to invest hours in watching someone play a game and then realize that you're not going to be interested in or you just have to go out on a whim based on what everyone else says and just try it. I've got a lot of open world games on last gen that I haven't yet played. Other than FF7 Rebirth though I'm not going to buy another open world game, may do what I stated above because unfortunately there are some good games that are built with the modern open world design, games like Dying Light or MGS5 Phantom Pain, to name a couple off the top of my head, even if I do think the open world makes these worse than they should be.