Just go read Y the Last Man instead.
Don't. Vaughan is, per his usual, full of shit ("i totally left the clues regarding definite cause of y chromosome extinction"), and that ending there is just ridiculous (last chapter, not the penultimate one).
Also, he
just might be subpar writer. He pulled similar crap in Ex Machina, and was present on staff during Lost 4th season conception. Runaways were mostly okay, but that's Marvel, so maybe he had good editor.
Bottom line is, his works sport strong beginnings, sometimes compelling middle acts, and disappointing finales. He's not even subverting reader expectations - which would've been fine - he's just shitting all over them. 'Member Sonia? That wasn't good storytelling.