BoA has 20+ years of Experience in the Industry, Eunhyuk has 15+ while Wooyoung is in his 14th year, they are all well known Idols in SK. All 3 Judges can give opinion as being experienced and still active in the Industry.
As there is no specific Dance Style for Street Dancing as it consists of many Style, just trying to get a Judge that is an Expert and is not boring is a huge problem for Variety Shows such as these.
oh no you should see some of boas comments she picked who was hotter she didn't pay attention to dance skills at all
the rest of them idk all i saw some comments she said....very weird