I can easily see the future of personal computing being a mobile device with peripherals that use its compute and cloud for anything serious. be that airpods, glasses, watches, or just hooking that device up to a larger screen.
theres not a great reason for an individual to own processing power in a desktop, laptop, phone, and glasses when most are idle while using the others.
The only things I can think of are you really want to keep all the data on your phone and don't want to use cloud sync solutions (Dropbox etc.), or you really want to save a couple of hundred dollars getting a (probably terrible) laptop without a motherboard. Not very compelling IMO.