The International Juggler's Association (IJA) has indeed hosted "extreme juggling" since 2006 or so. However, its description indicates it is not strictly an event where the goal is to juggle as many numbers as possible.
> Technical juggling skill has reached an all time high, but the most difficult (and most radical) tricks aren’t performed on stage. What if there was a place to show off these cutting edge tricks? This is a competition where jugglers on the cutting edge can shine.
> https://www.juggle.org/programs/xjuggling/
A google search for "ija extreme juggling" yields lots of entertaining results.
> The hard reality of every juggler is just: Do a few simple three ball tricks and people will get excited, show them your five ball routine they will fall asleep.
I believe others have mentioned this already but there is a lot of daylight between "doing juggling moves" and "doing juggling moves while being simultaneously entertaining". A little showmanship goes a long way, in other words.