I wound up installing the "Move Mouse" software to keep Microsoft Teams active. Seems to do the trick.
I used to show up as idle a lot because I have communications stuff like Teams on my (very slow, old, underpowered) work-owned laptop, and I do my actual work from my home PC. So the more I'm working, the less likely I am to show up as being active on Teams. But managers don't understand logic. They only understand a little green check next to your name. So... Move Mouse it is.