It is considered that the reason that 唐密宗, the middle-stage Mikkyo, declined and was interrupted is that Taoism--which was a rival having the same aspects of practical benefits in this world, as well as mojo--was favored.
中期密教である唐密宗が中国で衰退・途絶したのは、現世利益や呪術の面ではライバルであった道教が好まれたためと考えられている。