@LostInParadise Yes, the whole notion of transformative experiences is something that would fit right into existentialism. This isn’t surprising as one of Laurie Paul’s specialities is phenomenology, which is an important aspect of almost every major existentialist thinker’s work.
As for cognitive dissonance, that’s a good question and perhaps something that Paul should consider addressing. She would need to show what the difference is between someone experiencing choice-supportive bias and someone who has crafted their own preferences.
I imagine she’d say something like this: cognitive dissonance involves discomfort resulting from conflicting mental states, and choice-supportive bias more generally involves emphasizing a choice’s benefits and downplaying its drawbacks. Each is a form of self-deception. But a transformative experience makes it such that one can endorse the choice they’ve made even in full awareness of its drawbacks and the benefits of alternatives. The phenomenology is not one of reassurance.
This is clearly not enough, though. It’s an outline of a response, but one in need of filling out. I imagine a full response would rely on the claim that choosing whether or not to be a parent is a non-rational decision. The transformative experience leads us not to say that we had good reasons, but only that we are happy with how things turned out and can no longer imagine living otherwise. Alternatively, I suppose she could argue that choice-supportive biases are a mechanism of transformation. That would be an interesting route to take.