> Don't forget that your car may also have a cellular modem and rat out your driving habits to dealers, data brokers and insurers.
This is why I never drive a car I cannot repair myself in a pinch that requires zero software or even a working battery to operate, which means low tech, manual transmission.
> Stopped using X and all big tech services.
This right here. I haven't given up my cell phone yet, but I run GrapheneOS on a Pixel without Google anything and only with a handful of basic apps (OSMand, K9, Home Assistant...). If something can't be done in the browser, I pass.
Don't forget that your car may also have a cellular modem and rat out your driving habits to dealers, data brokers and insurers.