Did you have to a BCM to fit your 285's or your saying with your lift etc you didn't need to? I have a Pro as well and just changed out the suspension and now need tires, but I don't want to sacrifice mpg's or ride comfort for a bigger tire so my plan is to stay at 265 SL.
I ran BFG KO2’s E load 275-70-17’s on my 2018 Pro at first. Ride was slightly more rough, especially over bumps and since they weighed ~58 lbs. each the mpg took a hit of 1.5-2mpg over stock. Both city and street. The ride was quiet. I ran these without issue or mods initially on my Pro. Then I decided to add a 1.5/1” Cornfed spacers lift and then after that I went to 285/70-17 AT3W’s in a SL rating. No clearance or rubbing issues, smoother ride and no difference in mpg over the 275’s. Also, interestingly, your speedometer will be closer to correct with 275’s than 265’s. My 285’s are maybe 1 mph at 40-45mph. I have had C load 285/75-16’s KO2’s on my previous 2001 4Runner and the ride was nice. There is a slight ly better ride difference in a C compared to an E load. As I recall, the 275 Falken AT3W weighs ~57 lbs. This will affect mpg. The Pro wheels and offset, coupled with the fender liner mod done at the port on the Pros, will clear 275’s without mods or issues. I prefer the 285 look and performance better than compromising on 275’s. The selection and availability of 285’s as compared to 275’s is much better and a 285 will still fit in the spare area. Attached are pics with 275’s no lift, 275’s with the 1.5/1” spacer lift and the same lift with my 285 SL AT3W’s.
Hope this helps.