Getting an NPC to walk over to a bed, get undressed, lift up the duvet and climb in all in real-time is probably harder than it sounds. It's a lot easier to just have then collapse ontop of the bed (which, when you think about it isn't entirely unrealistic)
Sims 2-3 has it and not very hard if you bypass most of the climbing under cover the same way as you bypass switching from street clothes to armor.
This is actually a dead serious issue, multiple fights was lost in medieval times as it took time getting into armor, the chain mail had the benefit over the plate mail that you put in on like a sweater, plate armor was more comfortable and just as heavy but you needed help strapping on the pieces.
Fast forward 800 years and body armor is a major issue, they give excellent protection against rifle shots but are so heavy it's drains endurance and agility.
And little new is new, the grunts doing foot patrols prefer to use lighter armor than the once who ride. yes something changes, communication is a bit faster and it was dammed hard trying to get air support during the battle of Hasting.