I mean the original Sims. I've known several people who LOVE the sims - generally they use it as dolls, dressup.
EA keeps making new versions of the sims, generally they get worse with every generation. They become DLC-focused and less detailed. There's another sims game coming out this year, its gonna be F2P and probably suck even worse. The old games are still fun for people but they get less and less stable, they crash a lot, etc.
Also, people *love* to mod it, but, its just kind of a mess.
There's a FreeSO (Free sims online) which is just an engine, no assets. And the website is down. I haven't found a sims/dollhouse game that is free and open source. Is there one? It wouldn't be called Sims, I guess.