I don't ever recall seeing this. Certainly shouldn't happen on a 2019. My 2014 is fine.
I generally get paint touched up by the guy that fixes used cars. They are less expensive than regular body shops and do really good work since the buyer of a used car isn't supposed to be able to notice the repair.
I know that is a 'brushed' paint so touchup paint might not work. Might have to buy a new part.
Are there any other rusted seams? Search this Forum, there are other places where seam putty is not there and getting rusty.
Show it to your Jeep dealer, maybe there is an applicable TSB for the problem. They won't volunteer the information, you have to ask.
Possibly contact
@JeepCares on this Forum and see if they can help.