I'm sorry to offend halter people, but your breeding programs/ideals have produced travesties, IMHO.
I am another that agrees wholeheartedly with the OP. I can remember back in the day when many of the winning halter horses were also performance horses.
Heck, this guy was halter champion quite a few times at many AQHA shows...he was also superior heading and heeling horse.
This mare set Appaloosa history as a 3 year old at the '78 national show by winning at halter, get of sire, and WP.
This is the best picture I have of her without tack and it makes her look much more downhill than what she was.
And this horse was a multiple time champion in halter, WP, and calf roping
This guy was also halter and WP champion but he had the ability to do anything else you asked of him.
I think the best example of what a proper halter horse should look like in current times was posted in another thread just a few days ago. I mean, halter, WP, HUS, trail, reining, some jumping, and speed events like poles? How much more versatile can you get. The only thing he's lacking is some form of cattle event like working cow horse or roping.