I’ve found the “still occupancy” detection claimed by microwave detectors to be over exaggerated and even after tuning I found they false detect movement through walls or windows far too often. Gave up on them.
I use hardwired PIRs for 100% reliable room entry. Placement is key, you need to walk across the detection area not towards it. They don’t work reliably outside, neither do microwave or dual microwave and PIR sensors. For that I use on camera AI person and vehicle detection. This has been perfect.
Home occupancy detection is 100% reliable based on my security alarm state.
In bed detection is 100% reliable using Elevated bed sensors.
I don’t rely on room occupancy much for automation. Room detection for a few rooms is 99.9% reliable using Bermuda BLE and Private beacon tracking of my phone. I can also tell if my garbage and recycling bins are in or out on the street 100% reliably using Bermuda. However the more rooms I added to Bermuda the less reliable it became. Particularly because it cant distinguish between floors of the house. I can be right next to a beacon receiver upstairs and it will often report me as being in a room below. Having only a few rooms monitored at opposite ends of the house works very well though.