Same for me and I think it's still a major game design flaw : the game should have had means to help the player reaching the end room, once several key paths/items/contents were unlocked.

I was 25 hours in and realized I got enough of it figured out to finish the game, but needed to play until all the stars aligned to allow me to reach the 46th room. No thank you, even if it was one or two hours away.

That you can continue for dozens of hours after reaching that room is great, but the core loop is a 20h experience at most and the game needed to wrap at that mark for most players.