Slider all the way to the right, only hear demonic "Laurie".
So I end up interpreting the Yanny/Laurel thing through the lens of a pre-existing anxiety regarding hearing loss. I have no idea if that's actually the right way to think of it, but nevertheless it's where my mind goes instinctually.
I find that if I move the slider while the sound is playing, or if I move the slider really slowly, my ears stick to the last word I heard.
Another thing is that the speakers matter. I can't hear Laural on my laptop, but I can hear it on my phone.
I suspect this has to do with frequency aliasing and high frequency hearing loss.