I don't know much about software programing compared to firmware, but this looks exceptional and really inefficient
Pretty much. Even the parts that aren't necessarily
slow when it comes to performance, are still inefficient from a maintainability perspective.
That C# rewrite should've been an actual rewrite, rather than a simple translation. I and many others have said it before, and I'll say it again, Yandere Simulator isn't going to get much further with the mess of a codebase it's sitting on currently.
In fact, I'd go so far as to say that the game should be rebuilt from the ground up in a fresh Unity project. Not the story or assets particularly (although some may argue they need reworking too), but just the entire structure of the code and the layout of the scenes. Everything about the game screams inefficiency in both performance and maintenance. Even
if the game surprises us and turns out to be good, that doesn't do much when you can't play it above 20 fps.
Unfortunately, Alex grossly overestimates how much time such a reworking would take, so this is likely to never happen. I'd wager that you could get the game back up to its current level of content within a week or two, given a solid working schedule. Honestly though, it feels pointless to even discuss it, simply because of how unlikely it is for it to happen.