When I worked as a US FedGov contractor, I was greeted with a long warning banner every time I logged into my computer. The tl;dr version of it is “fuck your privacy”. Being that I was part of cybersecurity for the site I was working at, I was one of the people doing the fucking. While we didn’t read everything from everyone all the time, we were logging it and could pull it up, if we were performing an investigation. We also had some automated stuff scanning for patterns and keywords on a regular basis, which could trigger an investigation.
While I’m no longer in the FedGov space (thank the gods), I still assume that everything I do on my work system or with work accounts is being logged. Also, I’m still working in cybersecurity and am often still the one doing the privacy fucking. Yes, everything is being logged. We may not look at it today, we may not look at it tomorrow. But, when HR and Legal ask us about a user’s activity, we can usually be pretty detailed. Act accordingly.