How do 4's base game mechanics work?

brainybee

I have been reading a lot of notes on the tweaks and mods people are producing for The Sims 4, and I think I have a basic understanding of how the game's mechanics work, but I want to make sure. If how I think the game operates (recreating information every time there is a load screen or when players go to map or change families) and only spawning other npc sims when lots are loaded, then it kind of explains the way the game works and many of the bugs players are having (for example the game "forgetting" how people are related to each other, very limited story progression, sims left at home not continuing what they were doing, or their babies disappearing). It would also appear that there are many things the players are asking for that will never really be possible in this iteration of the game because of the way this works. Am I way off?