Let me put it another way...
A good friend came by with the ame question at the very moment I was processing the results of a shoot of Egrets.
As you know, blowing the highlights on such a bird is not very difficult. So I exp[lained to her that this was a negative, not a positive. That I could underdevelop nor push the film any way I wanted to..
She didn't buy it
So what I did was lower the exposure and the feathers on the Egret became visible. I then reset the dialogue to 0, with the highlights blown and brought it into photoshop. No matter what I did with the levels control, the highlights remained blown - no feathers.
This, if you pardon the pun, highlights the advantage of RAW.
And of course, there are a number of other aspects of the question, as has been pointed out.