Jefferson Airplane, The Who, CCR , Joan Baez, Crosby, Stills, Nash and Young were not well known?? Are we thinking the same Woodstock here?
Woodstock presented all of rock who mattered, minus the Beatles and Stones. The conversation should be, what big stars were missing?
Why it is celebrated above other such gatherings: it was held in the NY area so national media was close by and it surprised everyone by the scale (including the organizers) due to the fact that music had not been considered as important to so many youth.