Love how they look now but...
The watering mechanic is something I have a tinfoil theory on. It's no secret for a long while people have assumed gyroids had to do with graves due to the figures resembling
Haniwa. (Animal crossing is actually mentioned in the pop culture section!)
I personally keep thinking that the watering thing was added to separate that theory from the game due to how dark it was. Instead of just digging up funerary objects you now dig up what are essentially "weird magic plants".
Maybe I'm just overthinking though, lol.