Rust belt question

I currently own a 2011 that is on jack stands in the garage as a winter covid 19 project. It’s a good way to self isolate! This vehicle has lived 10 years in the Ontario rust belt without any undercoat, and I’m amazed how good the body is. It has no rust. None. Sure, the chassis amd suspension has surface rust, but that’s no big deal and expected.
I was just wondering if any of you rust belt owners have noticed whether some years of production are better than others for rust. Some older Jeeps around here are pretty rusty. Any thoughts on why some rust and some don’t? I don’t think it can all be related to frequent washing, lol. Although that certainly can help a lot.

 

Every spring I tackle the surface rust on the frame and suspension components before they convert from a surface rust issue. Rattle can Rusteoleum and/or some rust converter helps to keep the problem under "control" until the next spring. Some jeepers move to products like fluidfilm but I find the smell and mess it makes while working under the jeep undesirable. In some rust belt states the state dumps salt and brine preemptively whether the storm fizzles out or not so frequent water rinses help too.

 

Yes, I try to keep up with rust maintenance too, but I was wondering if certain years of production seemed any better than others, vis a vis steel quality, paint quality - whatever. I’m guessing some of the newer JLs for example, won’t survive the Canadian onslaught of sand, gravel and salt very well. Their welds seem low quality, the paint looks thin and poorly applied, and they give me the impression of a vehicle made in a hurry by a new work force. I hope I’m wrong! I just wondered if some jk years of production were better than others. Anyone have any experience with the range of years they were made? I find it hard to believe they were all made equal and consistently for 11 years.