I used to play with autonomy on, because I do like to have my Sims choosing to do things on their own. Particularly at a party or club. But, it got to a point where I was always finding myself annoyed because of the random stuff they would do. Have to pee? Go read a book instead. Baby is starving? Let's watch tv! I think I'll get in the hot tub... changed my mind I'll get a drink of water and leave the glass on the coffee table... I think I'll go for a swim... maybe I'll just play computer games in my bikini... nah, another glass of water, definitely. Oh, I'm married but I'm gonna flirt with that rando over there.
And it seems to take forever for them to stop doing an action when you cancel it and tell them to do something else. Sometimes it gets stuck in the queue and they just stand there. So I turned autonomy off.
Even with it off it takes forever to accomplish things. If a random Sim decides to strike up some idle chat, they're gonna be reading that book they've got for the next 5 hours and forget about actually finishing lunch before they need to be somewhere. And they love their musical chairs, musical beds, musical stools, heck, musical spots to stand in the building.