I think this competition is a good examples of what the author advocates for - asking the right questions, not the tireless ones. There's no specific prompt and no cliche single purpose to the exercise. Further, the competition is aimed at students - which means in all likelihood, most projects will be relatively short, succinct examples of cool things that can be done with the data (the door is not open to more data collection, to studies that require a lot of time, and the dataset is small enough that computing time/infrastructure should not be an issue).

The real challenge is having the creativity to come up with a question worth asking. From Yelp's perspective, I imagine the most value they get from hosting this competition is the (potentially monetizable) ideas for what types of business problems could be solved using their treasure trove of data.

I'm sure they could have their data science team build an incredibly sophisticated model for some specific prediction task (probably more sophisticated than what any student could reasonably submit) - but if that specific prediction task turns out difficult or not monetizable, that's a huge investment lost. Having many students look at many different ideas is more likely to result in finding the right question.