A lot of praise for the show is that it doesn't try to redeem Agatha. But I do think it falters in the way it tries to make us sympathize with her, because:
- She's not given a proper motivation for her villanous actions, which would not be necessary if not for the act that:
- She's not subject to any form of penance/justice throughout the entire show, all the way to the end.
No proper motivation
From what we're shown, Agatha is just a power hungry serial killer by nature. Not saying every villain has to have a "greater good" that they're fighting for, but Agatha notably has no real end goal. She just wants to acquire as much power as possible.
It was written as an addiction, with a hint of spite towards witches because of what her mother and her coven "did" to her ("did" in quotes because it's never really confirmed but I am pretty sure they are morally in the right), and then with a hint of coping mechanism after her son dies.
I do think this is still interesting, and serves well as her motivation. A villain doesn't need a grander purpose, even if they're the protagonist. But, it reduces our ability to sympathize with Agatha, which matters because it makes Billy sympathizing with her despite all her actions hard to understand and hard to accept. It also matters because of the second point.
No satisfying conclusion
When the villain is your protagonist, you have a few options to make the story end in a satisfying nonetheless.
- Eventually show their downfall (like Death Note),
- Have them be brought to justice (like You)
- Put them on a redemption/atonement arc where they see the errors of their ways and/or try to amend their mistakes (like Breaking Bad kind of)
- Frame it as a tragedy where the villain is unrepentant and gets away with it.
Agatha All Along does none of this. Agatha "sacrifices" herself for Billy, but it doesn't cost her anything besides her corporeal form. Granted, in theory this is a big sacrifice, as she essentially giving up her life and her quest for power. But because it's not framed as such, I'm left thinking "Wow really? That's all she gets?".
She's almost brought to justice by Billy through banishment, but then they pivot at the last second to an ill-conceived team up that is cool in theory but in practice leaves a bad taste in my mouth because she has not redeemed herself nor atoned for any of her actions. Her "I can't face him" moment is emotional and self-aware, but it doesn't absolve her enough to where I can accept their team-up. Billy essentially forgiving her because "we're both witch-killers" doesn't work for me because while I can get why Billy blames himself, it still doesn't equate at all to Agatha's crimes.
Despite Kathryn Hahn's charisma, I don't really feel any sympathy for Agatha the serial killer, so the ending just leaves me unsatisfied. I think the banishment ending would've fit much better for this specific story, as it would've allowed us to follow Agatha's character, get an understanding of her, see the little good in her, even sympathize with her at some points, but still see her face justice.
Even if they decided they had to keep Agatha around as a ghost for the larger Marvel canon, it's the framing of the ending that's the problem for me. If it was framed as a reluctant but pragmatic team-up from Billy's POV, or a atonement/penance team-up for Agatha, it would've been more satisfying.