It's not only those factors, even if all those exclusive PS games were only on PS5, it would still be weaker than the PS3 and even PS4 era if you want, The number of good games was just so much more in the 7th gen, and 8th gen as well. Now every big game is coming out once per 5-6-7 years. Back then we had big games every two years, for some cases even every single year. Also there were far more single player oriented games where now everything is looking for online multiplayer, and most of those games are online only and full of microtransactions. Back then almost everything was about singleplayer, and the multiplayer was just like extra. And even with that, that extra multiplayer was better and more fun than now.
My sales comparison threads:
Ultimate Showdowns: JP 2023 / JP 2024 / 2024 / 2023 / 2022 / 2021
Global LT Showdown / Regional LT Showdown / Historical Showdown / YOY Charts / 140M+ Club Chart / Quantity of Games