The ground effect has nothing to do with flying a Cessna 152 at 30 Knt with full flaps without stall. The change in the file brings back the old behaviour. That’s all Asobo will do with the next update. I’ll put my hand in the fire on that one.
The description shows how quickly the flaps can be fixed
(that’s what I meant by checking the facts 
):
Flight Dynamics Bug Details - Community / News and Announcements - Microsoft Flight Simulator Forums