Bfg ko2 in 34x10.5-17 is a really a 32.5 tall tire and my falken 255/80-17 just slightly taller.
Jadmt here has done a bang up job with tire size discrepancy. I've read a bunch of his posts on the JKU forum as well regarding how different manufacturers listed sizes dont always work out in reality.
a BFG KO2 34x10.5-17 is actually larger than a 285/70-R17 Ko2, and similar in size to a 255/80R-17 KM2 Ive also seen the "34s" next to a 285/70-17 Cooper winter tire, and the "34" is larger. Some manufacturers run closer to the listed diameter in SOME tire models, others don't. The Ko2s appear to run quite small.
Jadmt can pipe up, but I think it was Toyo tires that ran closer to true.
In my case I wanted a 33x10.5-17 AT tire, so wasn't bothered by the Ko2 running small.
I don't think wheels smaller than 17" are going to be making a come back, especially with brake diameter not likely to get smaller.