I would argue that people shouldn't upgrade every year if it's based on features alone. The features aren't enough. I upgraded my 11 Pro this year only because the Verizon deals were so good. I am happy with my 11 Pro, but I also love tech and love deals, so the 13 Pro, with the new form factor, smaller notch, ProMotion display and better cameras should feel like a new experience. That's the fun part of tech. I am blessed with 2 beautiful kids and a a beautiful wife and take lots of pictures so will be happy to see what the new camera features do.
The only issue with my 11 Pro is the the battery which Apple is replacing for free on the last day of my AppleCare coverage. They agreed it was 'bad' even though I was above their 80% capacity threshold.