'The closing keynote at the SCaLE 20x conference was delivered by 80-year-old Ken Thompson (co-creator of Unix, Plan9, UTF8, and the Go programming language).

Slashdot reader motang shared Thompson answer to a question at the end about what operating system he uses today:

I have, for most of my life — because I was sort of born into it — run Apple.

Now recently, meaning within the last five years, I've become more and more depressed, and what Apple is doing to something that should allow you to work is just atrocious. But they are taking a lot of space and time to do it, so it's okay.

And I have come, within the last month or two, to say, even though I've invested, you know, a zillion years in Apple — I'm throwing it away. And I'm going to Linux. To Raspbian in particular. '

-- source: https://apple.slashdot.org/story/23/03/18/237211

Cheers, Peter