Agree a 1/2 Ton will struggle in the power dept if you're pulling at altitude, but this discussion is like the guys that say you can't put a 11' TC on anything less than a 4500/5500 truck!
Look at the tire load ratings on the door sticker and then go buy some decent tires!
Or don't. I towed pretty heavy 12-15k with my last 2011 F150 work truck regularly for about 30 k mi. 1/3 of that pulling a 20' deck over 14k trailer and about 1000lbs in the bed at all times.
A set of timbre a kept the @ss end up and 60 psi in the crappy OE P rated tires kept it from bouncing too bad.
Didn't break anything. Didn't smoke the brakes or pop a tire.
Would a bigger truck have been more convienent? Absolutely
Was it necessary? Nope
If you are not putting a ton of miles on towing a 5ver then keep your half ton. Get some good D or E rated tires. Put your choice of support on the rear springs, brake controller and tow with confidence. 2k pin weight is not bad. Just keep it to a reasonable sized trailer, under 10k lbs and you'll be fine.
Now if you're full timing cross country get a 3/4 ton and you'll be happier.