PNW, I respect your take on this but keep in mind that you are pulling a 5th wheeler around. I too could not imagine using a half ton to do any of this.
The issue here is that someone asked for some advice. They clearly stated that they were looking at a specific size trailer. Their choice would make a half ton a legitimate choice. I have been towing smaller trailers around since the 80's. My current trailer has gone over 40K miles hooked up to my half ton Tundra. Half ton TVs are perfectly matched for many smaller trailers. I doubt I would EVER expect one to pull a 5th wheeler.