When the game modded by guradvillagers-1.20.1-1.16.0 , the iron golem will be able to float or move in water as other entities . Usually it may impact nothing , but if you are using a iron farm with lava clock controll , iron golem will die later than the time you set , and when the old golem is still alive the new ones won't generate. I know I could make the clock slower or let the iron golem away from villagers‘ detection range , but I like solve problem at its root. Sorry for that if this is a new feature I missed in the intro.

Intentional feature to prevent golems from sinking in lakes, you can disable this in the configs