Shelly BLU: lots of lost events. I have one on my kitchen. It mostly works to make the lights switch on when I walk in. Not always though, and when it doesn't it's a pain. It's also PIR alone, so small movements don't register. If I'm cooking, or doing the dishes, the timer runs out and switches the lights off. Getting them to switch on is a pain.

A bunch of Matter-over-Thread devices I have: hard to secure. I'll end up setting up a Thread Border Router on my IoT VLAN and get HA to connect to it, but that means yet another component to run separate from HA, which requires its own upgrade mechanism, backup, etc.

Matter-over-WiFi: haven't yet found one that would fit what I need. Will require expanding my IoT WiFi network to other parts of the house. My main APs don't serve IoT because a few tens of those would easily congest the radios, despite being very low bandwidth.

Most devices are PIR-only, or use subpar mmWave sensors, or a combination of both which tends to be hit-and-miss.

I haven't found a device that doesn't require a proprietary app for setup, which means tracking and the risk of them becoming e-waste.

I'm planning to build some out of cheap sensors from AliExpress and ESP32s but I haven't had the time and have too many other projects in flight.