Apple Watch not unlocking Mac
Well I thought I figured it out, but it stopped working shortly after.  So after much troubleshooting, I really did figure it out.  Wifi has to be enabled on the Apple Watch for the unlock to work.
It's funny that none of the apple support documents say that.  I just use bluetooth on my watch, so I tend to keep Wifi off.  When I reset my watch, Wifi was automatically turned back on, which would explain why it worked for a while.