[ska]

“The map is not the territory”

This is a similar sentiment, but perhaps more useful initially in conversation with people who may get hung up on what “model” means. It can also lead to a fruitful analogy as people easily grasp why different kinds of maps are important.

[dfee]

I’ve never heard this phrase but I like it.

[ska]

Some context: https://en.m.wikipedia.org/wiki/Map–territory_relation