Everything on the Internet is public domain.
If I disappear for 3 weeks, assume I’m dead.
It depends whether you can buy one anonymously - you probably can’t, I guess, as for what I know, providers tend to offer eSIM only with contracts and not prepaid options. Physical SIMs you can get on the street in many places, vending machines, eBay, wherever.
Tho there isn’t really any reason why eSIMs couldn’t be sold the same way, as it’s just a QR code.
The other problem is that in order to move the eSIM from one phone to another, it needs to be deactivated on the first one, which requires an internet connection. That’s more of a practical concern than one of privacy I guess.
They don’t record your every keystroke and such (that we know of), but they do log what app/program you open and when, how long you keep it open, if you’re using your keyboard or mouse, if you’re receiving notifications and from what applications.
On the phone, they know if you’re moving and where you are, can determine who are you with and such.
They are also trying to get you to use their web browsers, chat services, email, online documents… Why do you think they’re doing that?
Watching you wank isn’t super effective when it comes to targeting non-nsfw ads at you. They prefer to collect metadata (who, what, when, where) which is trivial, easier to collect en masse and analyse.
If it’s possible - you can limit the amount of data to some degree, but not entirely. Not just the OS is the problem, other people are. If some idiot uploads their entire phone book to every fucking service, you can’t help your phone number being among them and crosschecked to see who you know.
People do it all the time. The security concerns both with phones and computers is mostly the OS. So if the Linux is up to date, it’s good.
The issues may be insecurity vulnerabilities in the firmware and hardware, such as malware in the hard drive fw, but those seem to be rare, and newer hardware isn’t necessarily more secure anyway.
Most countries in fact, but you can get them if you want. Though I guess you never know if it’s not a honeypot operation.