The reasons given are pretty much a nothingburger and standard compliance items you should be doing anyway! I am trying to figure out what exactly is the problem people have though: you're literally on a company asset, being paid by the company, you've signed copyright away, you're aware their is no expectation of privacy. Use your cell phone or your home computer for home business, work during company hours, doesn't…
So, we according to the article, we are not only talking about screenshots and access to the computer's contents. I will accept a charitable interpretation that you are comfortable with a subset of bossware, but the article was talking about a wider swath.