They may think that if there was an incident that the jeep is not strong enough to take but those flimsy doors have nothing to do with strength. I had to uhaul dealer tell me I could pull there trailer with my doors off so I went home and put them on and came back for the trailer and you can...
That was the last set I bought and still have and the do work with a good view and I do use them occasionally when I don't have doors on but they seem to move around to much for me
I definitely like the 37s over the 35s for looks and wheeling and they seem to be better on the road but I'm not sure if that is because of brand change or going from a E to a D rated tire
I have tried many brands that are compatible with no doors and never found something that I could see the road good enough and ended up buy tube doors that I could mount at replicate of the original mirrors and that has been my go to set now, I sold all the other mirrors or threw them in the trash 🗑
I just went to 37s from 35s with no lift the only thing I added to get there was a complete set front and rear Hooke fenders and inner fenders which gave me a ton of tire clearance
I have pulled a 25' pontoon fully loaded for years I used to pulled it with my 2016 Sahara 4 door with 410 gears and now with a 2021 mojave with 410 gears and the mojave handles it great and I have never needed 4wd to get it off of any ramp.
You should be able to put 35s on it with the original wheels or different wheels with no adjustments no and no leveling kit, the mojave and Rubicon both have the high lift fenders openings to accommodate a 35" tire. I installed 35x12.5x17 on mine within the first month with no modifications