Did anyone read the last page? The only reason anyone is speculating Braviary has chance (read: not very likely at all but still existant possibility) of picking up any punching moves is because of the emphasis on his burly, powerful talons. He's one of the first birds to use moves associated with claws, fists, and otherwise great physical strength: Bulk Up, Crush Claw, Slash, Strength, Shadow Claw, Thrash, Hone Claws, and to a lesser extent things like Superpower, Rock Smash, and Rock Slide. Even though plenty of previous birds had powerful looking talons, they didn't really learn talon-based moves. Combine this with Sheer Force and his saddening lack of boostable moves, and some folks are hoping that GameFreak will allow him to be tutored the elemental punches when they are inevitably tutor moves down the line.
It's not similar to Togekiss, it's not similar to Gastly, it's in a class on its own in terms of probability. He is a big Pokemon, established to be incredibly strong through ability, movepool, and Pokedex text, with appendages that could potentially form a fist. Wishful thinking? Mostly. But I can see where it is coming from and hope (just for fun) that it does happen. Sheer Force's power boost would make the Punches, especially Fire Punch, nice tools in Braviary's arsenal.