Earlier quoted context omitted.
I’ve interviewed a few hundred people. Probably approaching a thousand, if not already. An interview is a scenario, and if you aren’t willing to engage in the scenario that we all agreed to partake in, that’s a huge warning sign that you’re going to be difficult later down the line. The point of the question is to have something remotely understandable for both sides to talk about, that’s it.
I also feel it's very easy for a good interviewer to bring the conversation back to the desired scenario. Anything from "imagine we are in a parallel universe where Google Sheets has not been invented yet" to "how would you design a google sheets competitor" would do the trick. Source: interviewed hundreds, incl FAANG.
I generally give it three goes with questions like these - the initial ask, and two clarifications. If we’re not getting anywhere I move on.