I agree that light pickup brakes are pretty good and lots better than just a few years ago. But will share my experience as it may be helpful to others.
Last year I towed a 8600 lb load (equipment trailer and small backhoe) from Virginia to California, with a 2012 F150 4WD Supercrew. I had good new brakes on both trailer axles (16 inch 8 lug rims so decent sized brakes). I adjusted them myself before the trip. I spent time getting the brake controller set right with the full load. Twice on the trip I had to brake hard to avoid a situation on the highway, and the trailer tires smoked, so I am pretty sure the trailer brakes were doing as much as they could. The load was within the pickup's tow rating.
There were two long down grades on the Interstate 10 route. From Flagstaff to Needles you lose 7000 ft in a morning's drive with some steep sections. Then again the same day, from Barstow to Bakersfield, you lose 2000 ft in a couple hours with some steep sections. I used the tow haul mode which downshifts the transmission pretty aggressively to increase compression braking. And I am a conservative driver, I was under the speed limit.
It didn't seem to me that I was leaning on the brake pedal particularly hard, but at rest stops along these grades the trailer brakes were hot and smelling, ditto the truck. By the end of that day the front rotors were warped, I could feel the brakes pulsating. It wasn't too bad, I lived with the warped rotors until 35k miles.
At that time I brought the pickup into the dealership to get things attended to before the 36k warranty ended. The service manager fixed the brakes under warranty. He said the front rotors were warped and grooved, and the pads were cracked, flaking, and even looked a bit melted in a couple places.
My conclusion was that, as good as the brakes are, they are not quite as robust as they should be to match the pickup's rated towing capability under heavy use.
