Your favorite Sims 3 Streamers on YouTube

I wonder whether Sims 3 or Sims 4 will be less buggy to play when Sims 5 and future updates of Windows are rolled out. Can sims 3 work totally offline? Can Sims 4 work totally offline?

-I cannot speak for TS4 because I haven't had a single second of personal interaction with it. However, TS3 is totally playable offline, especially if you have an all-disc version of it (pre-2012). When it comes to the digital version, I expect it to remain at the disinterest of EA. But at some point in time, TS3 is going to cease to be playable on newer machines with advanced hardware/software. Anyone who is a long-term TS3 player will eventually have to accept this fact and begin 'future proofing' their machines now for when that time arrives.

I am not sure which game to invest more time learning.

-Outside of becoming use to the controls of the game, there isn't anything to really learn.
TS3 relies on your imagination. When played to its strength, TS3 has the potential to become a proverbial 'Alice in Wonderland' rabbit-hole of sorts. What do you want? What do you wish to explore or experience? How much of your imagination and time are you willing to invest into it? This is the starting point to the game. How deep do you wish to travel into the capabilities of the internal AI? What do you want from your Sims? Whatever it is, they will return it.

I can honestly say from personal experience whatever you can imagine (and your PC can handle), TS3 has the in-game tools to make it so. True, for some things mods are needed, that's to be expected. More adult-type gameplay? Mods. More option for Sims or objects in the game? Mods. Tailored town progression. Mods. Un-promoted social (and private) behaviors. Mods.

When it comes to the Sims and emulation. What personalities do you want to foster? The sims don't have a scripted way of learning, they are data driven. They have four (x4) major ways of learning (what they see, what they hear, what they experience and, what you choose (or don't choose) for them. They take this data and decide upon a course of action to take. These actions build personality and 'lines of thinking'. They do have some 'scripted' reactions to events but once they fulfill that obligation, the true sim AI takes over and they show their 'natural reactions' to whatever event/interaction.

....And they have the opportunity to be more creative because they are not constantly repairing their games.

-TS3 is not without its problems. It does have its own set of unsolved game issues; some are due to the way the game was built while others originate from EA's neglect of the game and their consumer's concerns. Since the game is 14 years in age, most of these issues are known and have work-around, mod solutions or can be avoided altogether. Others are just what they are. Knowing this fact takes a lot of stress off of the player.