I'm not sure if this thread is still relevant, but had to post a comment after reading the title. I recently had the same issue with one of my older cars where the clear coat had failed pretty badly on the roof and hood. The paint was in great shape until my wife started routinely taking the car thru a car wash. I can't be sure if it was the car wash, but the paint was great before then.
A few months ago I applied a product that I came across that did an amazing job to hide the ugly white splotches where the clear coat failed. It's called L'Oxide made by Oxideoff. It worked great on my older burgundy car. It's been 2 months and the damage is still hidden. It's not a complete repair or a new paint job, but I can't afford those right now so this process was very acceptable to me, inexpensive and quick. Even if I have to apply it a few times a year, I'm happy to do it to hide those horrible splotches. There are a few YouTube videos online if you go to Youtube and search for oxideoff or loxide. Hope this helps.