Maya is not illusion, which is not there. which always exists is alone real. That which vanishes (Maya) is not. Yes, the vanishing phenomena is what is called 'maya'. The problem is that we take the world to be real, substantial, permanent and the source of abiding pleasure and happiness - which is the real delusion - since our common experience, which we share with all sentient beings is dissatisfaction, discontent and inability to achieve meaningful and abiding happiness. A condition which is known in Indian philosophy as Duḥkha.