"So tell me about a project at your last job?"
"I used Mapreduce to blah blah blah."
"So you had tens of billions of records?"
"Well, no."
"So why did you use Mapreduce over other solutions?"
"............."
And then I would follow up with: What would you do to make it a lot simpler?
You almost never get asked that in an interview though.
I'd love to be able to say this in an interview one day. And I'd be telling the truth (not about Mapreduce but something else, let me tell you about the time I lost an argument with a Senior/Staff Engineer who wanted to write an entire PHP library for log files on a single-serving linux host instead of using cron and logrotate).
But like you mentioned, it's a type of question I've yet to be asked. Depending on the room (ala "read the room") I might volunteer that bit of information in a more 'interview friendly' way.
Generally people tell me about the hot new XGBoost model they fitted, and I ask them how much better it was than logistic regression.
9/10 they don't have a good answer.
That being said, my favourite answer was from a candidate who told me that Kaggle contestants didn't use log reg, and therefore it was a bad choice.
Oddly enough, we didn't hire that candidate.
OTOH, I've worked at places where they wouldn't hire you if you didn't talk about your awesome neural networks/XGboost experience, so it really depends on the interviewer.