Well, it looks (from a high level poking around the internet) like Chromebook / Chrome OS should in theory be a good solution for most people if (and it's a huge if):
1). You trust the Google cloud to be truly safe for your data.
2). You trust that Google stores the data in the cloud well encrypted as advertised AND that they have no back door to freely look at your data (and profit hugely from access to all its users data, over time. Because, of course, no company would be incented to to that.)
3). You are willing to completely live within the ecosphere Google provides with you in the Chrome OS for docs, mail, etc., since it basically won't let you install anything outside that for the Chrome OS environment -- which wants to work in a clean sandbox each boot up, for security.
If you're willing to put up with all of that, then apparently you can copy small amounts of data manually to hard drives or flash drives connected to a Chromebook via USB. So you could then process such data in other PC environments like Windows, since Chrome supposedly can format the output drives in formats that Windows understands.
....
I think I'm going to get a book, a cheap Chromebook, and do some poking around.
All solutions look tainted to me, but at least my old brain can seem to grasp the Chrome environment, and not needing to constantly fight the security battle sounds refreshing after Windows on the internet.
In a couple/few weeks, I'll plan to report back here with a summary of what I think. My data is important to me, so others may as well benefit from what I learn. (And as a side benefit, if I can never have to fool with Windows 10 again, well wouldn't THAT be peachy!)
Given the track record of the perma-doomer blogs, I wouldn't bet a fast crash doomer's money on their predictions.