I would kind of be surprised if the chemicals were actually harsh enough to do any damage to the paint, especially considering how fast they are washed off.
I use Bilt Hamber Touchless, which has ph of about 12, as a pre-wash and have never had any issues. Sometimes during the winter, I just fill up a pump sprayer with 5% Touchless and pre-treat the car at a self service bay, then pressure wash it off. It is crazy how much crap it gets off all by itself.
Forensic Detailing Channel on youtube has a few really good videos on it.
He also has a video showing how paint sealants (wax, ceramic, etc) aren't really affected by a high alkaline wash.