I have played Firaxis recent XCOM games and also Marvel's Midnight Suns and I was pretty disappointed to hear that he left the company because Jake was kinda iconic to the XCOM franchise, many people associated him with it and with him gone the chance of ever seeing XCOM 3 looks a bit slim.
Anyway, for the games that he was involved in I did notice how there were some sims influences. You could design and customize your soldiers in those games. In XCOM: Enemy Unknown you could customize your soldiers, give them names and change their faces etc. In XCOM 2 and XCOM 2: War of the Chosen we could customize our soldiers even more, we could give them backgrounds and with mod support we could give the soldiers a lot of different looks, you often ended up giving your soldiers different personalities as well based on their voices. Soldiers could also form bonds with each other and after a finished mission you could take photos where your soldiers could do different poses, so the soldiers felt a bit like sims in a way.
In Marvel's Midnight Suns, which was the last game Jake worked on you did not have soldiers really since you were playing as super heroes, but you could form relationships with them and hang out with them.
Hearing that Jake wants to make a life-simulation game is both surprising and not so surprising. Surprising because I think a lot of people associate with him making turn-based combat games but not surprising because the games he have been involved in had sims-like influences so that might explain why he would like to make a life-simulation game.
