Not sure if my experience helps but I have a Feb 19 build Laramie Quad cab and reduced to no wind/road noise when on recirculation. With fan on speed 3 I could hear a pop when turning recirc off as the cab to bed air vents pop open, then it sounds like the passenger back window is open and hear road noise. Removed the rear seats and driving sounded like the passenger door was open when not on recirc, but still significant road noise. The seats really buffer the noise. I recently purchased the bed to cab seal that was left off newer build rams and it made a slight difference in cab noise but did not come close to solving the problem with noise. I have included pictures which show why the noise comes from the passenger side more than the drivers. The vent are located next to the sub box, the sub cutout in the carpet cover does not line up with the sub so the vent when open is directly open to the cab of the truck. So with no baffling the noise acts like a rear speaker sending road noise and open window noise into the cab.
I had everything apart so I insulated the rear of the cab putting material on the cab wall along with on the back of the carpeted cab cover. Biggest difference was from adding foam around the edges of the sub box to isolate the sub opening from the air vents. I used 3m tape and 1/2 inch pipe insulation cut lengthwise as the sub to vent seal. This made a huge difference in wind sound and road noise. Clearly another design issue, which shows up most in trucks with oem sub boxes.