The sims, for a while the greatest selling PC game of all time. One of the greatest selling games of all time period. So what went wrong in the Sims 3?
This is my opinion... The Sims is a virtual dollhouse, a little life simulator, a chance for anyone to play out a "what if" of their own or anyone else's lives, real or imagined.
And in the Sims 3, the sims themselves aren't relatable. Because they're always happy, and always have time for that thing you want them to do, and will always go for that jog. And that's not how humans act. We don't just "get up" go to work, do a perfect job, go home, work out, help our kids with their homework, write a novel, and kick back and relax knowing we are perfection incarnate.
We are not always happy, we are stupid little drama queens, silently or loudly. Sometimes we "just don't feel like a jog". Or are terribly upset, or... well hopefully we don't fall asleep standing up and piss ourselves. In fact it may be pretty hard to do that first one.
But our lives are full of conflicts, that are almost certainly small in any grand scheme of the thing, or even small scheme of the thing. But they're meaningful to us. And without that, with the Sims just being automata that will cheerfully always do as the big hand/clicky thing in the sky tells them to, they just aren't relatable. And the illusion that you're playing with a similurica of actual people shatters.
Sure "success" in the Sims 3 may be easy. But that assumes that "success" as we see it in the real life is what people want to replicate as easy as possible in The Sims. But being virtually rich, moreover in a simulation with ctrl+c and "rosebud" in it isn't as fulfilling as... actually struggling a bit to get there.
Further there are other goals, goals that are just as valid for players to want to achieve, as "success" in money or a hobby or whatever for their sims. Maybe they want their sims to be loud, angry slobs, or miserable failures, or etc. And maybe getting to the goal is part of the journey, overcoming obstacles is part of the journey.
It is for success, it's the only thing that makes success well, success in the real world. So when everyone in The Sims can be "successful" without trying or any obstacles, it doesn't really feel like success does it?
Now I don't know if your new "emotions" system plays into accomplishing the above. But I would hope so. And if it doesn't, then why wouldn't it? The journey of the game, The Sims or any other, is what matters. Endless gold for free, real or virtual, would make gold feel pretty worthless. Make the journey of The Sims 4 matter more, rather than just making it easy to "get" wherever you think the player is going.