I understand your frustrations. Unfortunately such a "record only when humans are detected" feature would cost a lot of additional trouble, because it would drain the battery. Only the passive infrared detector can be used 24h a day without draining the battery. As soon as the camera is switched on (even if just to send video to home-base for "human detection") it cost a lot of battery. So such a feature would drain your battery undetected (because there are no saved recordings).
Eufy extended the range that you can set the motion sensitivity to help some users and they said
So now you can the motion sensitivity from "far too low" up to "lots of false detection". Maybe they should have hidden this extendedrrange behind an "advanced settings" or so, no idea, I'm not a ui expert. But it's clear that you have to set the motion sensitivity to a reasonable level by trying out the "test mode", otherwise you will either miss events or it will drain your battery.