Thinking about how the one who chooses to take Jane's place as Redfield admits to her that they're scared.
And how the other is never asked the question because since the former had taken Jane's place, there was no need to continue the game, no need for them to answer. But the truth is that they're still scared, both of them, the one who sacrifices themselves and the one who has to watch them do so.
And the game is symbolism of their trauma and by playing it, they all have to face and confront their trauma and issues head-on. And by saying that you're not 'scared', they're finally able to accept and move on from it. But being 'scared' is a metaphor for still being stuck in your trauma and unable to move on from it. Like Jane is. And to let Jane move on, Noah or MC have to take her place as the new monster, becoming the one stuck in the past, while everyone else moves on.
But Noah and MC, the one who remains, don't move on. They never say it but they're still 'scared', still stuck on what happened that day, when they were unable to save the other. And so in ILB and ILW, we see they're still working on saving the other, their determination bordering on obsessive.
And that's what makes Noah and MC's relationship so, so, so important. The only way they can move on, the only way they can stop being 'scared' is by saving the other. They understand each other in a way no one else can because they're both still 'scared', arguably even during the epilogue of ILW. But they know that with the other by their side, they'll be okay, that someday they'll be able to stop being scared.