I'd only call it nihilism if you are in agreement with the grandparent and then do it anyway. Other choices are pretending it's not true (denialism), or just not thinking about (ignorance). Or you complicate your life by not uploading your private info.
not really, it's basically just being anti fragile. Consider any corporate entity that interacts with you to be an Eldritch horror from outer space that wants to siphon your soul, because that's effectively what it is, and keep your business with them to a minimum.
It's just realism. Protect your private data yourself, relying on companies or governments to do it for you is like the saying goes, letting a tiger devour you up to the neck and then ask it to stop at the head