Pickup trucks in general suffer from several significant barriers on the trail:
1. Wheelbase is generally longer than comparable SUVs, due to the pickup bed. This leads to increased risk of high-centering when cresting obstacles, and can expose the driveshaft to damage when the suspension is lifted.
2. Rear axles on pickups are generally centered on the pickup bed -- this is most appropriate for carrying heavy loads, but it also leads to large rear bumper overhang. Which means getting stuck at the BOTTOM of obstacles.
3. They are light in the rear when unloaded. It's less bad in 4WD than 2WD, but the rear end still slips around much easier than it would for a comparable SUV.
4. Pickup frames can twist between the cab and bed. SUVs are stiffer because of the continuous body.
A Bronco II (not a Bronco) is a surprisingly capable vehicle on the trail, even stock. 94 inch wheelbase, short overhang, well-distributed weight, etc. To do much better in stock form, you'll need a Wrangler, CJ, Willys, etc. Or an EARLY Bronco (they were substantially smaller).