This is nothing new. See the Great Disappointment; when that failed, people still believed him, too!
Well he did it before- claiming that the world would end in April…. of 1996! And people still believe him!!!! (in the same way that adherents of Jehovah’s Witness-ism still believe their folly ridden ‘doctrine’ in spite of the fact that their founder was dead wrong about the millennium and everything else).
As Jim West notes:
Only one word fits this guy and his followers- dilettantes.