It can definitely inflate ego, and people often misunderstand what ego death is (or the term can mean different things to different people).

In essence my understanding of it is that ego death is that bit when you stop having a past or future, the only thing that exists is the present existence. This is something you don't want to continue indefinitely, but can be an experience to learn from after the fact, it can also be something that leads to trip looping if you're not in the right environment for it.

If you've ever met the cliche psychedelic person whose so full of them selves, I'd say that their ego has been boosted.

Hell, I've experienced it whilst tripping; the feeling of having such a magical, almost holy experience that I felt Jesus-esque vibes when approaching some friends.

Also the whole feeling like you can understand anything you put your mind to is pretty ego boosting.

(Though a little confidence and some boosted ego isn't necessarily a bad thing if you suffer from low self esteem and anxiety)