Ego is needed at a point, how can anyone express anything without Ego?
Ego is needed by the mind-body to survive. It is part and parcel with its functions, navigating the material world, creating bonds with other social beings, creating self-concepts that try to make sense of the world to support the mind-body while offsetting stress.
The difference between pre and post awakening is that during pre, consciousness attaches to the ego as real, as "the person", as the true self. But ego does not have the solutions to suffering because it is holographic, it comes and goes. It's there one minute and gone the next. It is like trying to anchor consciousness in a moving target. We do this naturally after we are born. Pure consciousness attaches to the mind-body out of ignorance and reflex, and then it becomes so real-seeming that the "person" is seen as the Source. Later, you can use knowledge and direct experience to see that consciousness is not dual, the mind-body arises from it, but it is not the mind-body. Again, there's nothing "wrong" with this. Most people live their whole lives believing they're this person, this body, this mind, etc. Then they die and dissolve into the Om anyway. However, if you really want to know the truth, then that's why I'm saying all this. You don't need to know it. Nobody needs to do anything. Nothing is right or wrong. But as I had a natural inclination to know, and it was shown to me through life events, that's why I have pursued this path of knowledge... of trying to put words to it (inadequately).
Post awakening, it becomes evident that the true "I" is not the ego that comes and goes, it is Satchitananda that is omnipresent. It is the real you, the real self. This may sound weird to say but once the Atman becomes apparent, you can watch the ego in motion. You can watch the mind-body do the ego "I" while the real I just sits perfectly still in peace and equanimity. The day to day functions persist yet pure consciousness is always the focus. It's like how a candle lights up a room. The room then becomes full of apparent objects to study, explore, react to, attach to, but the source of light remains constant. The light is unbothered. This is the Atman that lights up experience. Once you realize that you've been the Atman this whole time and not the activities of the mind-body, it's possible to be liberated from suffering. It doesn't mean suffering ends, it means that there is always part of you untouched by suffering, even if the body is in immense pain.
Obviously there are going to be moments when you attach to ego, especially when emotions get strong, but with adequate training you will snap out of it really fast. I am still vulnerable to attaching myself to anger, for example.
Nothing outwardly has to change pre and post awakening, but the internal worlds are like night and day.
Ego is not evil. It serves a function. But it isn't capable of understanding the truth of reality. Eventually, the ego can be trained to sort of cooperate with the
knowledge of the truth, even though knowledge is not the direct experience. Ego cannot have the direct experience because ego isn't real. It is a hollow projection like the rest of Samsara. It has apparent realness, but it disappears and reappears all the time. The Atman doesn't. Ego cannot experience and directly know the Atman anymore than a character on a movie screen can understand the projector illuminating it. It does what it does in the so-called "karmic world" of action and consequence. It's like a program, a piece of software... it executes, opens and does all sorts of things, then it closes again. The Atman is present in the before, during and after. Even the strongest spiritual ego with knowledge of all the sacred texts, practices and methods is still just an ego. It will disappear at any given moment (i.e. going to sleep at night). But pure consciousness is always there.