Cheat Scripts exists and are ruining the Leaderboards
I just discovered that there are extension scripts added to the browser which makes people 'earn thousands of experience a day'. These scripts would ruin the weekly leaderboards and are totally unfair for those who grind xp to go to a higher league. Please fix these. I have a link to one such script.
3 ways to disable the Leagues: https://forum.duolingo.com/comment/33039989
The problem with reporting it is that too many people are doing it. Reporting users one by one is very inefficient, especially at higher league levels. For each user reported, there are another dozen that appear. The XP system is just plain broken, especially Stories and encourages spamming.
Also Duo has an achievement "Legendary" for winning Diamond, so they are encouraging people to do this to collect badges. Disabling leagues is sticking your head in the sand and pretending the problem doesn't exist.
The leagues doesn't make sense anyways. For some there are stories which gave a lot of XP in a short amount of time, the XP boost is only available for some, some can get bonus XP for doing a lesson and also the amount questions in one lesson is quite different. So just ignore the leagues an concentrate on learning!