Whats all this nonsense? You should absolutely temperature correct your M(DA). The chart has been designed, as others have stated, to keep you clear of obstacles withinin the temperaure range. The chart designer choses a min temp based on historical min temps at the airport and uses It if he can (ie if the GP is not too shallow (min 2.5deg icao) and obstacles do not penetrate the obstacle clearance screen).
If these conditions cannot br met then either the GP is steepened (increase FAF alt), the minimum temp is increased or both.
the M(DA) has nothing to do with this. The designer could in theory also correct the M(DA) for us By selecting the most conservative M(DA), ie one that will allow us to be at the minimum geometric altitude at the lowest temp. This however will be overly restrictive for most of the year when the temperature is above that value. This is why we must amend the M(DA)