Most likely, they're talking about paint crazing/checking. It ooks like small cracks in the paint. I'm sure if you ask, they'll tell you it's primarily in the darker colors on the coach, usually on the side that sat in the sun. This is caused by the fiberglass and is prevalent thru many years.
You can either live with it or have it repaired. In the past, the only repair was to replace the fiberglass, that bankrupted a couple of companies. Now, they can sand down to the gelcoat and add an epoxy primer and then repaint. This has been around for a few years, but not long enough to know if it is a permanent fix.
Many of the brands in that era also suffered from clear coat issues, usually along the roof line. It would "burn" or peel off. The only repair is to sand and repaint.
Don & Mary
2019 Newmar Dutch Star 4018 - All Electric
2019 Ford Raptor Crew Cab