The translation is poor according to a source on reddit. I mean, even just looking at it, you can tell the translation is poor, and not saying what is intended. SE wouldn't deliberately destroy people's furniture for exposing the housing bugs. This is not a threat, it is a warning that anything that is clipping with an aquarium could potentially be lost after the patch is uploaded into your game.
I believe it is a similar issue to placing too many interactable furnishings inside your home. After so many, some of said interactables, including partitions will just start disappearing. They are still there; you don't lose them and they and will reappear once you get close to the item. I am curious if this is the issue they are attempting to fix, which has lead to this potential problem.
Just make sure nothing is overlapping with your aquariums before downloading 4.3 and you should be good.