4runner, gx460, and the Bronco Raptor aren't great tow vehicles. I wouldn't choose to tow 5000 lb with any of them on a regular basis. If I was going to pick one though it'd be the Bronco Raptor. It has a better torque curve, 10 speed tranny, bigger axles, and bigger brakes. It's also wider and has a longer wheelbase.
Anytime you're towing anything with the mid-size there's more I worry about than just staying in the ratings. It's crucial to live the to a vehicle properly, trailer properly, slow down, and be smart. The people with the Bronco Raptor in question do that. We have plenty of friends that tow trailers with Tacomas that are well within the rating of the vehicle. Their lack of experience towing terrifies me despite them being well within the limits of the vehicle.
The people that have that Bronco have had some really good threads. Their F250 build saved me time and money. Hopefully they continue to contribute to the forum.
We live near an RV park. The things people get away with is mind-boggling.