

You can use an online tool to look up the Bluetooth [1] or Wifi [2] MAC of the device. If it’s espressive you’ve got one of their chips. That doesn’t guerantee that it’s not one of the others they make. You can also open up the device and look for the esp32. They almost always look the same with their metal can ontop.
The risk has been estimated as 0.3 out of 10
Don’t worry about it.
[1] https://ipnet.tools/bluetooth-device-address-lookup-tool [2] https://ipnet.tools/mac-lookup-tool
It ain’t so.
To use the “backdoor” an attacker needs to have full access to the esp32 powered device already.
It’s like claiming that being able to leave your desk without locking your PC is a backdoor in your OS.