It's not that it looks slow, it does a very good job at loading fast what you see first, and preloading the rest before you see it. The problem is that is keeps preloading and preloading content even after you've reached the end of the page, just in case you need it.
It is heavy but looks fast because you pay for it in advance, and it looks and works great. Well, except for the bit about needing an iPhone or iPad to see the airpods in AR, I'm sure it could have been done in a more compatible way.
Edit: gave in and opened the AR bit on an iPad. it's just a non-interactive 3D model of the opened case with the earphones shown, that you can spin manually or image in your desk and spin yourself around it. Nothing actually interesting.
It is heavy but looks fast because you pay for it in advance, and it looks and works great. Well, except for the bit about needing an iPhone or iPad to see the airpods in AR, I'm sure it could have been done in a more compatible way.
Edit: gave in and opened the AR bit on an iPad. it's just a non-interactive 3D model of the opened case with the earphones shown, that you can spin manually or image in your desk and spin yourself around it. Nothing actually interesting.