Fear of change? Hahahahaha
No, I just know what's involved, with the unpredictable "gotcha" a year from now.
Not to mention the knowns. Holy hell switching from Windows to Linux is very problematic for typical end users. Yes, the UI is that different, even with "friendly" distros.
You say your grandma made the switch? OK, so someone who uses a browser for everything and doesn't actually use office.
Let's see Libre office open an excel spreadsheet with tables.
Or edit a word doc and send it back and have it not be screwed up.
Not migrating is practicing risk mitigation. Hell, I can't change a single setting on work systems without validating that change in the lab first. And you want people to switch entire operating systems. For what?
So stop this fear projection nonsense.
(And I work with Linux every day on multiple distros).