I mean, exactly how invasive are default operating systems? (Like Windows, Mac, Chrome OS, Android, iOS) Do they log your keystrokes, log passwords, capture screen, upload your photos, videos, or audio? (Assuming you aren’t a target of government) Is it even possible for the average person who doesn’t feel comfortable messing with installing operating systems to have any privacy?
100% you make your own choices and the tools available offer various levels of true privacy. I do tend to agree that if you carefully select your hardware then roll a project you trust onto your system you are likely 1000x better than any off-the-shelf big-brother setup.
There is no easy answer to 100% verifiable and trustable secure systems at this state in the industry. Though I expect that to change over time, even lithography is starting to become a workshed hobby.