I think it's because most of the people on this forum have big(er) trailers so they think truck; for a good reason. Towing a 30' 10 thousand pound trailer with an SUV in most cases is just not reasonable.
If you own a bigger trailer most are going to think everybody else does too. Back in the day when my dad bought a 26' Layton, that was an average to big trailer. Now days that's small. I bet the average trailer I see on the road around here is 30' or so. People think you need a truck to pull those types of trailers; and you do, so they recommend to everybody to get a truck.
You don't have a big trailer. Your small trailer works for you and you no doubt can tow it with an SUV that is suitable for the task.
BTW an SUV now days is way more capable than pickups of yesteryear. my dad and I towed with a 69 Chevy half ton pickup back in the day. Drum brakes, 175 HP to the ground no air; you get the point. It towed great but todays SUV's with ABS and 325 HP engines would tow WAY better then that old truck would even think about towing.