Android Smart Lock: Why is there no option to use WiFi?

My Android device (v. 7.1.2) offers several options to use the "Smart Lock" feature. This feature uses some rules to automatically disable the lockscreen. Available rules are: - Trusted place - Trusted Bluetooth device - Trusted face - Trusted voice - On-body detection I am surprised that there is no option to use a trusted WiFi network. Some forums state the risk for the WiFi network to be spoofed. I don't understand how the risk is different: an attacker could spoof a Bluetooth device as well. What could be reasons for not allowing a WiFi-based unlocking while allowing Bluetooth-based unlocking?