Especially if you do a lot of travel, having to consciously partition what you use your devices for is just inconvenient. Circumstances differ of course. But I've never had an issue intermixing personal and work use.
What happens if your company realizes they need to track leaks of their data for compliance? Do they need to force you to install software that looks at every file you download on your personal machine?
Separate machines is better for both the employee and employer.
A lot of people don't have this issue, but I can't be the only one that does. I find strictly compartmentalising everything the only way to go.
Sure, if you’re careful enough with notifications that shouldn’t happen, but I’d much rather take a personal iPad with me on travel and never risk it.