I'd argue it's ignorance on the part of managers.

They're looking at time = productivity, and then they're the same ones that complain that people don't get enough done when they're measuring time first. Not results

There will always be people at your job that don't do a great job. They're less productive, they're less efficient, but you work with that. You understand that I will get xx amount of work out of this person each week, and you hold them to that standard. It might not be the "Jeff" level of work, but it's a level of work for Andy. If Andy doesn't meet the Andy level of work, he might need to work more, or be let go.

I don't think having computers purchased for you changes this. So many people put their personal stuff on that computer because they just don't want to, or have time to switch. It's not efficient. Especially not in today's world. I'd rather see them get the computer, be happy with it, and a VM with their work stuff on it.