I'm using chromecast for streaming to my television. But I accidentally cut my internetcord and guess what doesn't work without internet eventhough it doesn't strictly need internet? Exactly, I'm getting rid of the chromecast soon.
When streaming content to a chromecast it usually makes a direct connection to the content source, not going through the device you're casting from. In limited cases like when sharing your screen to the chromecast it does only go from your device to the chromecast without internet, but that's rarely used because it's power and data intensive to your device. I guess you're right on the internet not being 'strictly' needed but it's used for a reason.
Should still buy your own router though, and move away from google services 👍
All this is implying is that they are capturing this data anyways and offering you a peek at it for money with the guise that its for your safety.
There is likely no way for you to shut it off tracking you everywhere in your own home unless you pay them to access the settings for this feature.
They likely can track you behaviors with this and know when you take a shit, when you jerk-off/fuck your spouse, when you watch media, etc using machine-learning on the wifi specrum of your locations, signal shape, and duration.
Ask for just a plain modem and buy your own WiFi router. If that isn't an option, disable the routing functions and turn off the WiFi and buy your own router.
I haven't had a provider supplied modem or router in well over a decade. Not everyone has the know how to do this but it's not hard to learn and they should learn.
So I guess those directional MIMO arrays can now give information back to the host controller. That is kinda creepy but also it could be super useful in the right circumstances.