Is it true that commercial car washes are bad for your car's paint?

I think they are just being elitist, as “enthusiasts” of any genre usually are.
It is not like those car washes are using steel wool to clean the cars.
And you think the car manufacturers would make their paint job so flimsy as to be sanded off by by some rotating cloth machine?

I think car enthusiasts are washing their cars often and also are looking for a car to last decades so it goes into “classic” status. The average car owner is only owning their car for a few years and also is not necessarily looking to wash it once a week or more. I know with mine, if it goes into a car wash twice or three times a year that’s about it. I am not owning my car for decades, or looking for it to look good decades from now.

The older lacquer paint in the 70s and 80s was damaged by grit from car washes. It was also damaged by some cleaning agents.

The newer epoxies and UV cured paints are much harder and durable.

In earlier years, a lot of car washes used plastic streamer-like brushes that spun around the washer hub at a high speed. These would clean the car pretty well, but the ends of the plastic streamers could fray and could damage the finish like this

The last ten years or so, most of them have moved to a softer, spongier, flat piece of material to gently rub instead of hit.

THey have improved car wash technology so it’s less harmful to the car’s finish.

That said – a purist is never going to be happy.

Plastic bits that have paint can still be damaged by car washes.

In addition, frayed brushes or sponges, if not replaced frequently enough, will collect dirt that actually WILL scratch a car’s finish.

Brushless car washes don’t carry that risk, but the cleaning agents are much more caustic than the other kind. And those caustic agents would contribute to rust, underneath as well as on top.

I’m a car person. I’ve always loved them and take pride in my car. I wash it once a week and wax it regularly. If you keep it clean the paint will stay bright and shiny for more than a decade. If you leave it dirty the paint will deteriorate. I use a car wash that hand washes and drys the car. No brushes and no harsh chemicals. It’s not that a car wash ‘will’ harm the paint but rather that it can. Finding a good hand wash is not always easy but it’s worth the effort if you love your car.