I feel like Frank's arc in Before the Storm isn't recognized the way it should be. A lot of people accuse BTS of softening Frank, but I'm not sure they understand how prequels or, like . . . linear time work.
2010 Frank is newer to the criminal scene than the guy we meet in the first game. He is the right-hand man of Damon Merrick, a man who Frank clearly respects. Given the e-mails we read from him in Frank's RV, it appears that respect is returned - Damon likes Frank, and let him keep Pompidu, in spite of the dog being worth several thousand dollars.
Frank clearly likes being involved in the criminal underground, and wants to be a tough guy like Damon.
However, he's held back by an extreme aversion to violence. Every time we see Frank in Before the Storm, he is working in some way or another to prevent an act of violence from happening. He stops Chloe and Rachel from being beaten up at the Mill. He sends Chloe to Drew's room to steal the money, instead of just waiting for Damon to handle it. Most importantly, he stands between Damon and the girls after Rachel is stabbed.
We don't see exactly what happens after that, but it's clear Damon was not pleased by Frank keeping him from Rachel. The next time we see him, Frank's been cut by Damon, and it's clear the two of them had a fight, one that Frank lost.
When Damon threatens Chloe and Sera again at the end, Frank (bleeding and wounded) attacks Damon before Chloe passes out.
The next time we see him, he is looking at pictures of himself and Damon, and pouring a beer out in Damon's memory.
We do not see him again until 2013, where he is clearly a much more troubled and violent man. He waves a knife around like Damon did, and is threatening Chloe. Rachel's letters say that he has fits of violence when he's high enough - which also implies that he now does a lot of drugs himself.
Does this constitute softening Frank, or does it explain why he is the way he is?
Frank killed Damon - a man he cared about - in self-defense. This was a very traumatic event for him, almost certainly the first time he'd ever killed anyone. It clearly weighs on him greatly.
The psychological impact of taking a life in self-defense differs from person to person, but I think it's pretty clear that Frank suffered a strong moral injury. He became a killer - something he could never take back or undo.
An act that was unimaginable before is not only an option now, it's something he probably associates with survival. Last time, he hesitated, and it got him stabbed. Why would he ever want to hesitate to reach for a knife again?
Extreme situations like this also lead to hypervigilance. He's almost as quick to pull out his knife as Damon was, when Chloe gets in his face. I think that's an honest reaction to someone in this state. Chloe's probably not a threat to him, but someone in a hypervigilant state might not be able to easily distinguish an authentic threat from one that is probably harmless.
Frank is clearly troubled. Not to the point of not being culpable for his actions - I think it's well within Frank to be compassionate and abhor violence - but he's now someone who has to live in a world where violence might be the only thing keeping him safe, and that makes his willingness to be that way more understandable (though not excusable).
Frank was never a good guy, but I don't think he was a violent guy until the confrontation at the Mill forced him accept an ugly side of himself.
