I think the most primary thing of all is that, most people don't have the means to run Ethernet cables to places that typical cameras are installed (doorbells and garage floodlights)

It's a catch 22 though. Ok one hand, every single person in my neighborhood has multiple cameras on their property now and even when I lived in an apartment complex, everyone had a camera at their doorbell, but they all are usually ring or some other subscription based, phone home type.

Do WiFi cameras present a new attack vector, yea for sure. Is having a WiFi camera that could be disabled better than not having a camera at all (what was the reality 5 years ago), hard to say.