Interesting how you consider it ego-bolstering. Can't you just ignore the leaderboard?

It seems a lot of effort goes into making this tutorial. The guy working on it seems to be running a business. Although it can be done without requiring a sign-up as you said, I also understand how the author would like more people to sign-up, follow the competition, and potentially use his company's service.

Writing good tutorial is actually pretty hard and time-consuming. Just making it open and not getting any benefit out of it is not a sustainble business.