I've mentioned before on here, that I just insist anything of mine that's brand new, isn't touched by the dealers. (that includes any courtesy washes after warranty or service work) My T6 was terrible, and needed a lot of work before we sealed it. My previous Vivaro was actually much better, and the paint was far more robust. My Motorhome is full GRP, which tends not to swirl up anyway, but the acrylic windows will do very easily if the dealers use incorrect equipment. My wives Mini was used and actually really good, but then it is Cream and doesn't show the issues as bad as all my Black vehicles.
All our business 'Paint seal' work that comes to us (Caravan and Motorhome only, as that's what we specialise in) We always insist the dealers don't prep the exteriors, and leave everything for us, which is a much quicker job than fixing the issues potentially caused by the dealers.
My latest MK7 Golf which was only 12 months old when I purchased it from Sytner is in a shocking condition and looks like the previous owner used a scouring pad to wash it. This wasn't obvious when I glanced over it at point of sale, (outdoors and wet from rain, but I trusted it was fine from previous experience with Syter) but when pointed out to my salesman, they did offer to have the paint corrected for free, but I decided if they would allow a vehicle to come out of a dealership to a customer in that condition, that it was the last time i'd be using the dealership (that was the 7th car i'd purchased from that exact dealers, including 4 other BMWs) So it still sits looking awful, and I will get my own trusted detailer to rectify the issues.