While this isnt the first ending I did, I think From should have made it so that if you dont start new game+ when it asks you, you should start before owl and choose to disobey the iron code.
I've played this game 4-5 times, and I never get tired of it. But it does really suck for people who have chosen this as their first ending, they were locked away from a substantial cool part of the game and have to play all the way through again to get to it. Kinda just feels like bad game design imo.