There most definitely is perceptual hue shift in HSL (and HSV); it's illustrated quite well at [0](The blog of the creator of OKLab), particularly in [1], an image showing S and L axes while leaving H fixed.
So first, thank you for the correction. It's fantastic to learn something new. And second, do you have any idea why the OKLCH example on the page is so atrociously bad? The way blue changes to cyan is even worse than the HSL/HSV difference of blue-purple. It's like the cure is worse than the disease. If they were so concerned with hue fidelity in the first place, I'm surprised they wound up producing an end result just as bad.