Hiring funnels at big companies are funny because they're all about stacking filters together in a way that optimises some random grab bag of metrics in the candidates who make it through.

One of those metrics is "number of people hired who literally can't write code". You'd be able to give these candidates a full description of what the median is and they still wouldn't be able to finish this question, and you're not going to get too many false positives, so you add it to your rotation as the first question and have an enthusiastic mid-level engineer do it as the first half-hour round of an interview.

Then you design a few more rounds to test for the positive things you want, like pair refactoring, architecture, lunch with the team, or whatever floats your boat. That way your senior engineers don't need to interview people who can't write code and you stand a lower chance of accidentally hiring some of them.