Welcome to club of lat 80's vehicle owners. The problem you describe is common across car lines. In order to meet EPA requirments paints were reformulated.
I have a 88 XJ and due to an accident it is getting a full body paint job. I think 19 year olds shopping and driving should be outlawed...
It was an extra $1000 to paint the whole vehicle over fixing the rocker panel, quarter panel and replaceing a back seat door. Tomorrow it goes into the paint booth.
They guys at my body shop told me the paint failure was caused in part by applying clear coat to the color coat before it dried.
With an inteact clear coat no problem, but when the clear coat fails in one spot then the atmosphere gets to the partially dried paint. You and I know what the results look like.
I had the same problem on a 89 Buick Century but it spent it's first 8 years in a garage so not until it was 12 years old did the paint begin to fail.