Usually it causes a lot of problems to introduce a bunch of variables into an existing save that was created before said variables were a thing. It's different for something like Pregnancy (which starts at 0 and can be flagged 'on'), but Turn on/off sounds like a World Generation thing and likely can't be retroactively added. So in that save, all NPCs would have Turn on/offs set to empty as they'd never have received values for them during worldgen.
Think of it this way. Suppose there's an NPC described as Devon Glover. You may see them as 'A toned slightly dressed up brown-haired college boy. ' until you learn their name, but their name in that save is always going to be Devon Glover when revealed. Turn ons and Turn offs would be similar to that in that the NPCs should already have received that information during worldgen, it's just that you (the PC) haven't learned that yet, so in your save they wouldn't have any and neither would you unless there was an ingame way of changing your Traits.
My two cents, anyway.
Edit:
I stand corrected. As soon as you wake up on 0.5 loading an older save:
View attachment 3702013
Not sure if it applies to NPCs too, though they already have Likes and Dislikes so i may be overthinking it.