I assume the code was just too old and convoluted to maintain properly. I'm a bad coder so I've definitely redone parts of my scripts from scratch rather than trying to refactor them.
Then again I'm not a small billion dollar indie company who's main focuses are spying on users and helping to commit genocide.
In the case of terraria I feel the game's become a bit overstuffed. Bosses like dear clops and the old one's army event don't fit neatly into progression and there are plenty of items that seem redundant since you can get a better version in 10 minutes. Obviously this is a minor complaint by someone who's been playing terraria on and off for nearly half my life but I do wish they worked on a full sequel but I doubt that's ever going to happen.
I've completed Stardew valley twice and I don't feel like replaying all the same character interactions. It feels a bit depressing to build up relationships the second time. That's why I'm so excited about haunted choclatier.
I do want the developers to work on what they're passionate about and I am glad they've supported these games for so long but I do wish they just let them rest.