It's significantly more work to run around the nest, and it requires more intentionality than piloting a drone and being stupid about it. There's also usually signage warning you to not do the running-through-the-nest thing.

For obvious reasons, we can't hang warning signs in the air.

I have my doubts that a license will prevent people from doing stupid things, but that is (at least part of) the reasoning for having a license - so the government can say "told you so".

It's on par with immigration forms asking you if you're planning to be a terrorist. It's a useless question, but it establishes a paper trail that somebody has told you not to do that.

It's like rooted in Lambert v. California, which stated that you can't convict a person of violating a law if there was no probability they could've know the law existed. A question, or a sign, or a license establishes that there is a probability.