I suspect a lot of it is down to the rider. I have spent 40 years riding in the Alps working my way around thousands of switchbacks, many were narrow and tight, and I've never fallen over (so far) - and yet I'm not very good at doing U-turns in parking lots. I have practiced parking lot U-turns on my 2018 Goldwing (like I did on my ST1300, ST1100, Ducati, Guzzis, etc.) and I am no better and no worse on the GW than I was on any of the other bikes, which is not very tight.
On the other hand, I do see a lot more of the 2018 - 2026 GWs in the Alps than I ever saw with the previous generations. I was particularly awe struck about 3 weeks ago when I was standing in the parking area at a tollbooth for the Timmelsjoch (a private Austria/Italy pass road). Two riders on late model GW Tours (judging by the colors maybe 2024s) approached the toll booth, stopped about 15 feet before the booth and decided for whatever reason to turn around and not go through. They both flicked their GWs over to the right like 250cc Enduros and effortlessly U-turned in less than the width of 2 parking spaces in a couple of seconds - I wish I had a video of it. Clearly the rider has a LOT to do with how the bikes handle.
My wife and I were 2-up on a 2026 rental R1300RT - in my personal opinion the best iteration of the RT yet, faster, better handing and loaded with technology. And yet, I would not trade it for my 2018 GW Tour with the Traxxion suspension and BT Moto tune. The GW has a noticeably lower center, handles well for US roads, now has the power and throttle response it should have had from the factory and is more comfortable than the RT. It's also the only bike that I have ever owned or ridden where a driver's backrest for lower back support makes sense for long trips. I'm 75 y/o and it still works for me. It's a keeper for the foreseeable future.