Re: Hands up who is still a fan of IoT?
Even if you disconnect YOUR WiFi, what's to stop someone else setting up one from outside your premises that your devices can nonetheless reach, and indeed they may be able or even REQUIRED to do so as a Whispernet, which you'd have no ability to turn off unless you'd like to live TEMPEST-style with no windows.
I'd open up the bulb and cut the antenna. Not possible to open it up? High enough induction current will fry it anyway. Plus the added bonus of returning it just before warranty expires -- can't open it up, can't prove I did anything nasty.