Abby is the most unjustified antagonist-turned-protagonist in all of fiction.
I mostly enjoyed TLOU2 but it falls apart upon reflection, because all the way to the end they're trying to build up this "redemption" that never happens. I really think at a very early point in concepting TLOU2 Neil Druckmann hired Halley Gross and they circlejerked about LGBTQ character-inserts and buff women, and they flirted with the idea of not doing a Joel/Ellie sequel but one about Abby, and ended up starting filming. At some point they convinced themselves to marry that scenario with their Joel & Ellie continuation... Maybe some Sony rep said "You have to bring back Joel & Ellie" and much like Kojima did, much like Shu Takumi (creator of Ace Attorney) did, Neil Druckmann felt no desire to do a full sequel about Joel and thusly said "Yeah... okay, I'll bring him back... to kill him, and this new protagonist will do it."
And I think it's a damn shame because if you imagine everything with Lev and Abby in isolation of the premise of TLOU2's plot, you can imagine a game where, while it's not as interesting for TLOU, it's an alright adventurous story about a flawed woman who seeks out redemption and finds some friends that need her... but once you make that the unfolding event to Abby killing Joel, it starts to fall apart. You have an unjustified killer of vengeance meandering around in a transphobic tribal war with kids, and it's somehow supposed to be TLOU2.
I loved the tale of revenge with Ellie, and I liked the flashbacks and I liked how it resolved with Ellie and Abby. I did not give a shit about the Wolves, the Scars or Lev because it felt like it did not belong in this story. And I so strongly suspect this came into existence because Neil and Co were playing around with other ideas for potential non-Joel&Ellie sequel concepts.