The equipment is indeed defective. If your receiver is able to be overloaded by adjacent channel interference because you as the designed neglected to install

The equipment is indeed defective. If your receiver is able to be overloaded by adjacent channel interference because you as the designed neglected to install a bandpass filter on such a critical piece of equipment, and it wasn't discovered until later when someone legally was granted a license to use adjacent spectrum, your equipment is WILDLY defective. Just because it took many many years to identify the failure doesn't give the manufacturers a pass. A jammer is a malicious, unlicensed product specifically designed to prevent your Wifi from working.