The ego is who you "think" you are. Your "false self". Your "self-image." Your "True Self" is who you ARE. And who you ARE, you ARE ALREADY. AND HAVE BEEN ALL ALONG! Namely, one in union with God. Operating out of the ego is necessary for early stage development. But staying there in the main into adulthood is essentially "not growing up". It's stunted. People have "successful" lives at that level. But it is a level without wisdom, without authentic loving relationships. Because everything is about the self-serving trinity of "me, myself, and I." At the most self-serving level, it is called narcissism. And even Presidents get stuck there. And it is toxic when they do. So frankly, it is delusional to claim the ego is merely an illusion. For when it is most fully active, it is dangerous to be in denial about it. The denied ego is dangerous because left denied, it becomes evil.