There is a lot of misinformation out there or positioning. At the end of the day, 37s fit on 35s have been driven really hard and jumped to prove it. If you want to order factory 37s and blue leather seats for 8k more vs investing that money with people like SVC, RPG etc who could really improve the off-road performance of your truck, that is your call. The 37 package is a great package for many. I wouldn't say the trucks at the same money aren't equally capable because that is not true-I would def give the advantage to the 35 package with 8k, BTW, the full-size spare fits but likely a bedack with two spares is a better call if you are that serious an off-roader.
All of that said, look at the Gen 2 and Gen 1 builds that have been done on this site with serious kits on them that are WAAAY more capable than any Gen 3 with the 37 package.