I can see it. My corporate work laptop is locked down with their security and monitoring software, so I’m not using it for personal things, even if it is allowed for some limited things. And there’s company resources that I can only access through the machines under their control, so I couldn’t ditch it either. And using that laptop for a second job would be a big no-no.
I can see the school laptop being similar, though my experience is that they tend to not be locked down quite as hard as the corporate machine, unless you do boneheaded things with it and piss off the school’s IT department.
So I can see the need for a personal computer, plus it’s always nice to keep that well separated to avoid things like incidents hooked up to a projector and screen sharing.