I think you're being very shortsighted. "Most people" haven't even had a laptop for a single decade yet. Most people have had one for 1-10 years I'd say. Also, "most people" haven't had desktops for more than a decade and a half.
What on Earth makes you think these form factors / devices will still exist in most people's homes for decades?! To me, "decades" implies at least 20 years....
So do you think, in year 2031, we'll still use desktop computers? That's crazy. No, we will have moved on.
Keyboards will be out-phased for most users by 2031. I image maybe devs will still use them, and they'll be common in specialty scenarios, but they won't be for "most users".
> they'll always be on your desk at work
Also shortsighted. Workstations will evolve too, even if this is slower.