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IMO it depends on what you're carrying, for how far, what season, and about 100 other details.
Had a car with a 4x8 utility trailer. Now have a ex-cab full-size 4WD pickup with a 6.5' bed. I prefer the pickup. So easy to move bikes with, especially dirt bikes. And extra especially ice bikes. In the winter the snow and crap gets thrown on any bike in an open trailer or hitch carrier. Bike stays clean (and salt free) in the bed of a truck. Truck with bike in back is more maneuverable, easier to park and costs less @ the tolls than a trailer setup. I argue it is more secure than a hitch carrier or trailer.
Randy is over selling the tail gate thing. Put the bike in diagonally if it is heavy or long. Or just cinch the tailgate half closed if not. I just got back from a 1750 mile round trip with two dirt bikes down south. Bother were in my truck parked straight in and strapped against the front of the bed. We had gear and boxes between the bikes and could have fit a 3rd bike easily. Tailgate was ~3/4 closed and held in place with an extra cinch strap. Worked great. Gear stayed put even through some mind blowing monsoon rains in Worcester county.
Trucks and dirt bikes go together great.