This is the most likely reason. They should have put a sign, but the ramp looks right to me if you want them to match pedestrian speed when merging into a pedestrian space.
I am an Engineer and have done things both ways throughout my career. What is easy to miss in digital are the overall holistic design and the way it all fits together, because you are always zoomed in on a particular piece of the puzzle and rarely see the whole thing on screen in a meaningful way. There is just something about seeing a full design laid out on paper, spread out on the table, that lets many little things jump out at you.
https://www.youtube.com/watch?v=wsZ6YPsPpj0