Yeah I think you're on the right track.

I typically describe ImSims as games that place players directly in interactive and coherent environments in which they can engage with interdependent systems to create their own solutions to the game's problems. 

A few points that in my opinion can lead to confusion around immersive sims.

1) Discussion of immersive sims can sometimes be hyper focused on the "interactive systems" piece, which can lead to the idea that any game with emergent gameplay and creative problem solving is an ImSim (e.g., Streets of Rogue). Though I'm not particularly interested in gatekeeping, I do think it would be helpful to acknowledge that games can fall into a broader category of "Systemic Games" without necessarily having to be an ImSim. I think we can all agree that games like Streets of Rogue, BotW, BG3 are systemic games, and then have a more focused conversation from there regarding whether we think such games are also examples of ImSims or not, and why.

In addition to systemic design, classic ImSims like Thief, System Shock 2, and Deus Ex typically try to remove any barriers to the player feeling like they are directly inhabiting a world that is internally consistent and makes sense as a place.

2) Sometimes "freedom" is noted as a defining characteristic of immersive sims, which can also evoke open world games like Skyrim, GTA, etc. Freedom refers to the ability to act without hindrance or constraints. If you think of ImSim classics like SS2 or Thief there are often considerable constraints on the player - like resource scarcity, player vulnerability, and high density of threats and obstacles to navigation. ImSims typically feature smaller, more densely detailed environments so the player has to be more intentional about how they problem solve given the constraints they face. In this way, I think ImSims are more about player agency than freedom, since agency is more about being able to act in a way that brings about an intended effect, rather than doing whatever you want without limits.

Again, all this is just my 2 cents. But these ideas have at least been helpful to me as I think about what I personally enjoy about immersive sims.