I have no problem with the concept that I can't expect privacy in my communications if they are done with my employer's equipment, period.
I am much closer to agreeing with you on this one. However - there should be limits. My telephone at work is my employer's equipment. No one from higher-up management has ever told me one way or the other whether my phone line is tapped, but I would assume it is not. If it was, and I got called on the carpet for something I said to someone in a personal conversation over that phone (whether during business hours or not), I would be less than pleased. I feel that I have a reasonable expectation of privacy when I use the phone at work.
I also have a computer. We are expressly told that (1) we are not to use the computer for personal purposes and (2) our use of the computer is subject to being monitored from the network center. Fair enough. Of course I totally ignore this, and crawl all over the Internet whenever I have some free time - if I ever get caught (haven't yet in 17 years), it'll be my bad.
I guess it has to do with that phrase, "reasonable expectation of privacy." What's reasonable? That has been the subject of decades of litigation.