As much as I like the article, the title is flat-out incorrect. The most difficult bouldering problems aren't found inside a gym, they are out in nature. World Cup problems average V10ish, whereas the top climbers project V16 outside.
It literally says those things. It says boulder problems go up to v16, and that they aim for v10 at the comp.
Both grades I don't even aspire to!
https://en.wikipedia.org/wiki/Grade_(bouldering)#Comparisons...