Penny wise and pound foolish, plus a dash of NIH syndrome. When you're the only company doing something a particular way (and you're not Amazon-scale), you're probably not as clever as you think.
Most business have static sets of data that people load on their PCs. (Why do you assume laptops?)
The only weird part of that question is that 6TiB is so big it's not realistic.
In my view, it's an appropriate question.
OP even mentioned that it his favorite 'tricky question' . It would def trick me because they used the word 'stack' which has specific meaning in the industry. There are even websites dedicated to 'stack's https://stackshare.io/instacart/instacart
The largest dataset I worked with was about 60TB
While that didn't fit in ram most people would just load the sample data into the cluster when I told them it would be faster to load 5% locally and work off that.
You don't get extra credit points for mind-reading, if anything you get more esteem for requirements-gathering, which would lead you towards either a professional solution or a laptop solution: whichever fits the business needs.
It might be a totally unreasonable question if it's provided context-free as a form on a screen, but it is a perfectly reasonable conversation-starter in an interview.
You tricked candidates with your nonsensical scenario. Hate smartass interviewers like this that are trying some gotcha to feel smug about themselves.
Most candidates don't feel comfortable telling ppl 'just load on your laptops' even if they think thats sensible. They want to present a 'professional solution', esp when you tricked them with the word 'stack'. which is how most of them prbly perceived your trick question.
This comment is so infuriating to me. Why be assholes to each other when world is already full of them.