Earlier quoted context omitted.
If your relatives are significantly tech illiterate, I'd skip the smartphone entirely and go for a locked-down Linux desktop + feature phone. The most dangerous apps are big legitimate ones. If you do go for a smartphone, my experience tells me that there's no difference between Android and iOS. The biggest sources for shady apps are the Google Play Store and Apple App Store. Shady stuff on the web can be easily defe…
Sir a Linux desktop recommendation for non-tech-literate elders is just silly
With a well-supported hardware configuration and a working web browser, even a non-techie may have a more stable experience than they would with Windows.
That has as much to do with the decline of Windows as with the ascent of desktop Linux, but still.