Oh, it's not nagging at all. At least I'm not seeing it as such.
The question I would pose is "Oswin is being convinced to try what?" because that's something maybe I'm not understanding. Florencia is the one who's like "Oh how interesting, let's fuck around and find out" and throwing caution to the wind. Even though Oswin is being compelled towards accessing the elixir, he's not actively trying to use it. He's just making it available for Roswell to choose.
Well, that goes to show how this scene has confused me. Without her experiment, the medicine is just left sitting there. The risk of it being lethal remains true in both scenarios, which is reasonable motive to hide it in the first place. So what has changed that opens this option for Roswell in spite of the danger?
Roswell isn't in control anymore. Dave remembers, so everything Roswell had been tunnel visioned over, everything that he'd 'decided' was now incorrect.
This is why I feel that there's no good way of explaining this without having a mini-lecture on quantum mechanics in-game. Roswell observed reality as him being doomed to die, so it was true. Oswin observed his medicine was a failure and that saving his son was out of reach, so it was true. Florencia as an agent of chaos decided to test this and thus didn't observe anything beyond seeing her family needing saving from themselves but within herself was incapable. Dave recalling the events of the game observed an option and existed as a contradition to Roswell's observation. If Roswell was observing reality one way but concrete proof in front of him directly contradicted it, his reality flips to the inverse: He's not doomed to die. In the same way, Oswin's observation in light of this is the same, flipping to 'his son can be saved, his medicine wasn't a failure.
Florencia, who understands quantum mechanics, decides to open the door witnessing the way the universe is now being observed and thus opens the vault in the same way we open the box and see if the cat is alive or dead.
Ok, so Dave remembering Roswell's many failures offers a new perspective that prevents the disasters to come. That part is the easy one. How that also subverts Oswin's perspective of the medicine being a failure, still eludes me. Honestly, i find it would have been easier for Roswell to interject in that scene, now with the the broken paradigm, to express he wishes to try the medicine later on. It wouldn't be weird for Oswin to go along with it seeing as he is pretty lenient with Roswell in general.
To do that within the scene wouldn't be appropriate with Roswell grieving over losing Thanatos though. While in supplementary material Oswin is lenient and lets it be Roswell's choice, there isn't room for it in that scene and by the time we've moved on, Roswell isn't present to deliver in dialogue what he wants.
Yeah, unless Thanatos deactivation could be done at a slightly later point. The vault might also not be so deep Oswin revealing the medicine would be out of earshot. Either way, i can presume the discussion with Roswell to happen off screen. But, i still feel like it would be more organic for Roswell to bring up the option rather than Oswin. I guess the only way you could show that is if later at the hospital or the vacation, for someone to comment that this conversation did in fact happen. But that's about it, i don't see many comments concerned with this specific point, the ending might be just fine as is.
It has its problems, but just a lot happens in a short span of time and a lot of things depend on other things. The vault opening kills Thanatos. So Thanatos cannot just go offline later if we want any sort of view inside of the vault; which if we don't do that then we'll have people always wanting to have seen what's inside in the events of the game properly. At the hospital, Roswell still hasn't decided if he's taking the medicine because he hasn't spoken with Oswin properly as far as the risks. If we move that conversation forward then him grieving Thanatos and the loss of his friend and confusion about what's happening alongside Dave telling him he needs to seek help is all lessened to have a monologue or side comment about him making another choice. The point was that Roswell was not in control anymore, the choices aren't his to make in the game anymore, he needs to let go.
