This issue is not just with OA's. Those pics could have been of my boat, I had/have virtually the identical issue. The great majority are not spider cracks in the traditional sense as they are not caused by stress and do not go deeper than the actual gelcoat, the laminate is perfectly fine.
I believe TDun is mostly correct, aside from the gel coat being very thick, I also believe that there is an incompatibility issue between the gelcoat and laminate resin used. As to why the extreme gel coat thickness, it was undoubtedly done to prevent print-through because they chose not to use chopped straw. This was not an attempt at saving a buck it was an attempt at quality. Unfortunately it backfired on them.
I have found that approx 70% of these areas can simply be sanded out and when finished with 1000 grit wet sanding and polishing they are virtually invisible. The balance requires such aggressive sanding it breaks through the gelcoat exposing the yellow laminate and requires spot spraying with paint to hide. Incidentally the reduced gel thickness from repairing / sanding these areas seems to prevent it from reoccurring.
I further do not believe this is entirely an issue triggered by sun exposure, I am under cover.
Both Ocean Alexander and Albin are supposed to be high end, high quality boats but it only goes to prove once again they "all" have their issues be it rusty tanks, leaky windows, blisters or all of the above. You either find one that has the work already done or find one that needs work you can do.
Personally Gordon, I wouldn't worry about it unless your finicky about cosmetics. If you are, I would walk away, you will never recover the 50K cost to paint it. In 10 years it will need painting again by the next owner and you gain nothing. At least this one still has the "original" gel coat and you don't have to deal with several layers of old flaking paint.
In my case I tackle one area at a time but mostly I only think about doing it while relaxing on the aft deck with a cold beer.