If it didn't take up so much space on the hard drive, I'd still have Red Dead Redemption 2 on my PS4 despite completing it twice.
I've also replayed all of the Fallout games, including 1 & 2 at least twice, on different platforms, as well as Elder Scrolls 3, 4 & 5.
But I've never removed Subnautica, despite completing and platinuming it (which is fairly easy to do). I just like to dive back in and visit all my old bases I built (one of which is massive, so I could have a safe entrance connected to an array of tunnels that takes me up to an observation room where a few reapers constantly circled.)
I can't say the same for Subnautica: Sub Zero