When I'm saying "I am here" is a fact, I'm saying that to the layperson, that is how they express their understanding of the word. Fact is truth, and not something to be iterated on, added to, or improved in any way. So to many, saying that "God is a fact." is very agreeable, if not obvious.
When you talk about approximate geometry, physics, or chemistry, that is very different from the deceitful language games being played by groups in American society. And when we say that evolution is fact, that's not even playing the game right, and it is said in bad faith.
When someone can equate God with Fact and get wide agreement, or agreeably express their understanding of fact by saying, "I am here. That is fact." (arguing against this is a trap), you will lose if you say that evolution is a fact, because evolution cannot stand on the same place as God, and saying so is a cultural violation.
Furthermore, facts can never be changed or improved upon, nor reframed. When someone says that God is Fact, they mean to say that God is unquestionably true in an unchanging and objective way. If you say that evolution is fact, someone will ask how the THEORY of evolution has changed over time, and how a changing theory can be fact. They are deliberately switching back and forth between technical lingo and vernacular. If you try to elucidate with anything less elegant than how the conversation went so far, you will lose.
This game, this abuse of language, this struggle for political power and social configuration, is very far and apart from the pedagogical motives of approximate models in physics, chemistry, or geometry. It is done in bad faith. It is done as a game. And even if you were fully cynical and believed that gaming is the right way forward, even then this is the wrong move. The stronger play would be to instill this contrary framing of language at an early age through an authoritative institution -- schools.