They definitely each have their own strengths and weaknesses, if I had to pick a winner, I'm going with Steam Deck, you just can't compete with their controller API and the Deck's assortment of input options; that alone makes everything else obsolete.
Raw horsepower(Rog v Deck) is a meaningless metric; Using the Rog is like driving a 911 without tires, just rims; you literally can't control it.
hard agree. although i haven't personally tried the rog ally, i just don't think i can ever go back to a handheld without trackpads and the ability to customize controls with such granularity. though those leds are pretty sexy...