Earlier quoted context omitted.
I've never really worked in a cubicle (once had a mid tower PC and dual monitors acting as partitions to the front and left) but wouldn't an advantage of an open plan office over a cubicle be that you can see your manager walking towards you from a mile off and be able to quickly look like you're working.
These issues sound a lot like managers not trusting employees to get work done, which sounds like a bigger issue.
Managers should trust their employees to get stuff done, and not micromanage their time. Employees should get stuff done whether their managers are watching their every move or not, and, trust their managers to not be micromanaging their time. We both need to create a trustworthy relationship.
I have no sympathy for employees who do not do work without being forced to any more than I do for bosses who want to micromanage every minute of employee time or every website they visit. You're both hurting all of us.