Yes. Wi-Fi security cameras can be disabled without touching them. A cheap handheld jammer or a deauthentication attack can knock a Wi-Fi camera offline in seconds. Once the wireless signal is disrupted, the camera stops recording and stops sending alerts. This is not theoretical - it happens.
Deauthentication attacks are the most common method. They exploit a weakness in the Wi-Fi protocol to force a device off the network. The tools to do this are free and widely available. This is why Doberman only installs wired PoE systems - the camera does not need to be physically accessed, and the attack can be carried out from outside the property.
Wi-Fi jammers are another option. They flood the frequency band with noise so the camera cannot maintain a connection. These are illegal to use in the UK, but they are easy to buy online and impossible for the camera to defend against.
Even without technical tools, many Wi-Fi cameras can be defeated by simply unplugging the router or cutting the broadband cable. If the camera relies on your home Wi-Fi to function, anything that takes out the network takes out the camera.
Wired PoE cameras avoid all of these vulnerabilities. They connect to the NVR by Ethernet cable, which carries both power and data. There is no wireless signal to jam or deauthenticate. The only way to stop a wired camera recording is to physically cut the cable - which means getting close enough to be recorded in the process.
This is one of the main reasons Doberman only installs wired PoE systems. If a camera can be disabled from across the street without leaving any evidence, it is not doing its job.