Maybe, as I see later also in lemmy.bestiver.se. But not all users are following all lemmy instances-
Zerush
Fungus rules them all
Google even in this way logs your activity, because half of the internet, apps and services, apart of YT, use Google APIs, like google-taskmanager, googleanalytics, doubleclick.net and others, not only the Google services. Google permiys to manage and delete all this data, naturally it don't say it and only few user know it, in the Google Dashboard. but only if you have an account. It's a mess, but Google (Alphabet INC) is everywhere, you can't avoid it completly, even avoiding its services, except using exclusively i2p or other descentralized apps and services. Google has had too many years a complete freedom to dominate the internet and ending its "don't be evil".
That isn't "something bad could have happened", but "how much has already happened" because of this.
You can't with an OS full controlled by Google or Apple. You can only alleviate the problem, using alternatives, such as LinageOS, Ubuntu Mobile, de-googled Android or another distro, but only if you have root access. https://www.pcmag.com/picks/break-away-from-android-ios-7-free-open-source-mobile-oses-to-try
Yes, if it tries to escape from the plate.
Phones are spyware by definition
Only good if it still moves.
Too much 404 Brains in the US
Also cool the Doom.pdf