I know youngsters who dont even have an email address. Though, this may change if they have to enter the workforce.

Lot of people using their office-notebooks at home, even if its not allowed. Most people out of tech do not have big hardware at home anymore.

Do you work in tech by chance? I work in an entirely non-technical field (to the point we barely use email), and I have several coworkers whose only “computer” is their phone or a tablet.

A smartphone is the main / only 'computer' for a lot more people than you think.

This is complete conjecture on my part, but I bet if you're late 20s - early 40s, you probably have some form of pc/laptop laying around. But people 50+ (gen x / gen boomer), a phone is likely all you use or own. My mother, aunt, et. al operate totally through their phones. The same is true for my pre-teen, teenage cousins or cousins children (ipad generation).