Protect or will the area underneath be a different colour than the rest of the truck with some sun? One year in the Texas heat and that sticker will need to stay on for life or you’ll have a permanent colour variation.
Btw what kind of rocks you encounter do a curveball around the fender flares? Are you running an extreme offset on your wheels?
Yeah I can see if the truck is exposed to extreme heat where you may a different shade of color. When we run out in the desert, the dirt sandblast anything in its way. I'm running stock wheels and I still get some debris hitting that specific area you have decals on. I have PPF'd that area as well as the lower rocker panels and run mud flaps. My FIL has a completely stock Raptor, doesn't off-road and he has rock chips in the same area. If you don't intend to off-road the truck then I guess the risk is minimal.