I completely agree. The Dawn wash is more harm to the car than it is good.
Here's my reasoning . . .
-Why bother using Dawn to strip wax? If you're doing a Dawn wash you're likely claying and polishing afterward which will remove all the wax/sealant on the car anyway.
-Dawn is a degreaser and will pull oils from the plastic/rubber trim causing it to discolor or prematurely crack/degrade.
-Why bother using Dawn on neglected cars? First Dawn does not provide the lubricity a true car wash soap does. So, you're likely instilling marring. Even if you're going to be polishing afterward you could possibly be making the paint worse necessitating the removal of additional paint. Just spray the car down with an effective cleaner like
Meguiar's Body solvent to loosen up the
grime before washing.