At 60, I applied to Canonical and got hired. The hiring process is thorough but very fair, all WFH, and they generally don't care about personal attributes. Gave me 20% above my asking price and a higher starting rank than expected.
I thought Canonical was the place where every candidate had to write a bunch of essays and talk about how they did in math in high school (regardless of how long ago that was).
Glad you had a good interview experience there, but it's genuinely the first time I've heard of it happening.
I interviewed with Canonical in 2023. It was an enormous waste of time. I would never suggest anyone interview with them while they still have the same interview process.
I would struggle to have a polite response to that question. Come to think of it, the last company that even asked me about high school was a horribly toxic place, and it'd be a red flag that this wasn't a place for me.