HomeKit Accessories list does not include some devices shown in the Home app

I'm attempting to control a television (an recent LGTV) via HomeKit. When I scan all of the accessories (through HMHome.accessories, and also by querying each room separately) most of my devices show up -- but not my TVs or Apple TVs, and a couple of other things like an AVR.

These devices show up on my Home app, assigned to specific rooms, and I can use that app and Shortcuts, to control the TV.

Is there any way to find these devices through the HomeKit API? Or are there other APIs which I need to use for them, perhaps AirPlay?