Painted aluminum is the worst, and with the environmental/health issues eliminating the use of former chromate primers, it's even tougher.
Very much explains the Trek observations, since 1980 is when chromate disappeared.

The aircraft industry is smartest about defeating it using modern primers.
I once worked on the American Orient Express with it's 70-y-o aluminum coachwork when it was parked at the local train station. and wrote a patch repair procedure.