This is why Windows will get away with it.

As much as Windows is deeply flawed, the user interface challenges with Linux are difficult to overcome. Until there is a version of Linux where you don’t have to open the console, Windows will keep its market.

> Until there is a version of Linux where you don’t have to open the console

This is already the case from the Grandma use case, i.e. nothing more than a web browser and maybe Thunderbird and an office program. The terminal issue doesn't come up until you start getting into people who know just enough to be dangerous (myself included).

The larger issue is that computers with Linux pre-installed are (within a rounding error) not a thing, and thus Grandma can't go out and buy one. And even if she could, would she place her bets on a (to her) completely new computer system? Not without help or solid recommendations from trusted sources.