1. The concept of a model is entirely unproblematic in this forum.

2. In that entirely unproblematic sense, neither a thermostat nor a cruise control contains a model.

From a computer programmer's perspective, a model is something that reflects the state of something else -- even a trivial single value like "the current temperature" or "the desired temperature".

If a thermostat only had a desired-temperature knob or only a "current temperature" indicator, I might agree that there's no model. A thermometer and a control knob don't "model" anything, in that there is nothing "reflecting" them. In the programming sense, there's no "view" or "controller".

But the moment you make something depend on these values (which in turn depend on the state of the world), it's pretty clear in programming terms that the values are models.