Also Kespa did a real good job marketting their players to the point where players like boxer, yellow, shark, flash, jaedong were literally celebrity status in Korea.
Big corporations will support kespa because of all the revenue these players generate.
Esf tried hard but the game lacked the hype and excitement BW did, also its competing in a pool of widely support esports scene where they need to fight for viewership with dota, lol, wow or w/e people play and BW never had such problem.
Also esf tried to garner MC that celebrity-esque status but just never really came close. Very few players have television personalities and even if they do, there arent many places on esf where they couldve displayed that personality.