I wouldn’t compare the two. Factoring in the range of bombers, different bombing techniques (e.g. blockbusters followed by firebombing) and different aims of air warfare and land warfare, the destructive power of air raids is devastating. Think of Tokyo on the 10th of March 1945 - not to speak of Hiroshima and Nagasaki.
Aachen indeed was special, also because to the best of my knowledge it wasn’t as heavily damaged as e.g. Cologne by the time of arrival of ground forces, and there was a significant strategic value to the city which made it important for US ground troops to control the city. The Battles in the nearby Eifel, by the way - far off from larger cities - were even more fierce, for the same reason. Afterwards, other cities on the way to Berlnin weren’t as completely destroyed by ground troups because their strategic value for the German army was significantly lower.
However, this is of little importance for your original claim that cities in the east were more severely destroyed, and your additional statement that the destructive power of aerial bombardment is a persistent myth. I want to explicitly underline that I am not trying to downplay the destruction caused by ground forces, especially during the Soviet offensive movement towards Berlin. But I am very doubtful that your claims would hold under scrutiny. Destruction of industrial centres was very severe, including the Rhein-Ruhr area, the Weser-Fulda-Werra area, and the lower Elbe area. And this included centres of habiation, not only industrial parts. Central Cologne was basically flattend with the exception of the cathedral. Bochum, Dortmund, Hagen, Essen, Duisburg and many others had lost 50 % of their buildings. The eastern part of Germany had its share of heavy destruction, but I don’t see where your idea of a “myth” comes from. The tonnage of explosives deployed to destroy the capital (NB!) of the Third Reich doesn’t really convince me.
Also, Berlin was a special case. If you compare the Battle of Berlin with the Battle of Vienna, this should become clear. Quite some damage in the latter was caused by German troups blowing up strategic buildings. You can find similar patterns in the destruction of Warsaw in 1944, in which artillery shelling played but a role among much stronger destruction as a measure of retaliation by the German troups. The case of Berlin is more related to, but even less devastating than, the situation during the Siege of Budapest. This, in fact, is a very strong and vivid example of the destructive power of artillery. Last, not least: if you are referring to number of people killed and maimed by land and especially urbarn warfare - then I probably see where your line of argument is coming from.
