I'm a well read grad student who's bluntly honest about all things, although I try to be most honest about myself.
Matt Murdock, aka Daredevil, calls Laura by her name, and a child, and a victim of what the Weapon X program did to her. (So does Wolverine.)
Captain America calls her X-23 and says that even though she was brainwashed, punished, and a trigger scent was used, she has to be held accountable for the murders she committed, starting before her teens, and all planned and coordinated by the Weapon X program. (Who took fifty million and up for each murder, so she was a weapon, and a business, to them.)
Matt does call her a weapon at one point but more in 'this is what they wanted her to be and trained her to be, and how dare you hand her over to S.H.E.I.L.D when you know they'll continue using her as a weapon?' way. He acknowledges her training, and the fact that she was used as a weapon and assassin without wanting to continue using her, or even punish her because she didn't want to kill any of those people and was sometimes compelled to via extreme Pavlovian training. (And this conversation starts with 'she could have had a normal life with Wolverine; we should have left her with him.')
But apparently Captain America is a subtle absolute dickhole. I don't know if anyone remembers, but he also treated the idea of therapy glibly to Deadpool. (Although Wolvie doubled down in that by dismissing Deadpool completely. In that scenario, Dr. Strange was the dude who came out on top by putting his hands on Deadpool's shoulders, and saying out loud that he was human and deserved to be treated with compassion as every human is.)
But somehow Cap is an even huger dick in this scenario. Stop doubling down on the dick behavior, Cap. And this is why rigid morality/moral cornerstones of universes bug the crap out of me. Cap's 'murder is bad' line? Good. But if all he's going to see is that then no. (And he doesn't. He actually is okay with killing if someone is going to kill more people if they aren't killed, but will look for every single other option first. He also is down with self-defense. This, however, is an extreme case. Laura's actions were self-preservation: she knows how badly she'll be tortured if she doesn't perform to expected parameters. I wouldn't be surprised if implied death threats or direct death threats were used, and I'm certain a case could be made for her being afraid for her life by age nine with an underperformance. In fact, during one of her first tests, although supposedly out of her earshot, it's said that if she can't perform she's no use alive. This is in response to accusations that the exercise is killing her.)
There are no easy answers. Everyone truly responsible is dead, and while Matt is correct that she shouldn't be imprisoned, or worse used as a weapon again, even leaving her with Wolverine may not be a solution. (Well, it is, but Cap also has a point: she's killed so many people they can't just let her disappear. They need to monitor her, make sure she doesn't resort to violence again. And I'm not saying that this is her fault, but that when push comes to shove, it's easy for her to use violence, or even death, as an answer. She's been trained to think it is, and not only that, the way to keep from being tortured. Not only that, her own dehumanization helps that attitude along: how much easier it must be to think of others as objects when you've been trained to think that way of yourself.)
Again, easy answers are presented, but they're either too moralistically rigid, or worse than you'd think - S.H.E.I.L.D looks good on paper, but, yeah, they'd continue to use her as a weapon, or too simplistic. Simply leaving her with Wolverine and Xavier isn't really an answer, especially for Cap. Beyond the rigidity in thought, he's seen her first murder scene, and actually helped her to escape when he believed she was the handicapped girl she was posing as during her first mission. Cap is haunted by that, and haunted by the thought that because he wasn't able to stop her, every murder she's committed since then was at least partially his fault. Despite the fact that he knows how she'd be used at S.H.I.E.L.D, he also knows she wouldn't be killing innocent people there. Despite the fact that she'd be a prisoner and a weapon there, much like she was at Weapon X, the gratification of having a murderer put away (and the self-satisfaction of having been the one to put her away) and the certainty that she wouldn't be killing innocents must be tempting for him. In fact, it's probably what's making his double think - Weapon X program bad, S.H.I.E.L.D doing the same thing good - possible.
Man, there's a lot to mine in this series and it all came out.
Also, Captain America: huge dickhole even before he was a nazi...