After reading it again here is my interpretation:

What is meant by "self-taught narrative" is a narrative of their experience in which they are "self-taught" i.e. taught themselves.

It could be easy to assume a "self-taught narrative" is a narrative one teaches themselves i.e. a narrative that is subjective, self-assured only, and thus not valid; but I don't think this is what is meant.

Hence, the line:

> Other self-taught narratives

Are not "other narratives I taught myself" but rather, "the 'self-taught' narratives of other people".

I think this is implied by:

> My self-taught narrative is not other peoples’ self-taught narrative

note the use of a singular "narrative".

I think the contrast/revelation of the line "This was a bombshell" is that this:

> is a completely valid narrative, but a path that is predominately for women

i.e. this is what she discovered, and still believes, and forms the basis of her rejecting her former contempt.