I'm completely comfortable with the idea that The Sims is an RPG under my definition.
Sims actually has a lot more roleplaying elements in some aspects than say Mass effect or Witcher, no joke. There is quite a bit you can learn from Sims, it IS an RPG, a sandbox RPG without a metaplot.
No. Sims are not RPGs. They are literally simulations. You can choose to role play your simulation, but that doesn't make the simulation a roleplaying game.
I could be playing Sim City and I guess that's a role playing game because I am role playing the mayor?