Good point.
But to ascertain the truth requires there to be a method for doing so.
In the case of an invisible god, you need faith. Faith isn't a criterion that leads one through reason to truth. It is a kind of assertion in spite of the lack of evidence. It is, by definition, not based in reason.
If truth is not ascertainable through reason, it may be true but one cannot derive it for what it is.
Therefore, from the perspective of establishing truth, god is a bit of a non-starter.