What if the modular computing evangelists at Framework decided to make a handheld? YouTuber Pitstoptech has largely answered this question by building a “fully upgradeable gaming handheld” around one of Framework’s upgradable motherboards.
Pitstoptech intends to prepare and sell handheld DIY kits “soon,” based on the prototype design you see in the pictures / video.
The Steam Deck doesn’t have a discrete GPU either. Though this was with an Intel chip, and they don’t have anywhere near as good onboard graphics as AMD.