Why do some people perceive alternative spiritual teachings as a threat to traditional religion?

According to Osho, alternative teachings threaten traditional religion because the old guard—priests and the elderly—are invested in the status quo; if the new is right, their authority and identities collapse. Conditioned, rigid minds fear the unfamiliar. True religion is always fresh and rebellious, so innovators like Jesus or Buddha provoke backlash until their message hardens into another establishment.