This assertion implies that faith-based religion is irrational. Perhaps better said that faith-based religion can not be proved or disproved by the scientific methods (of course not, then the religion could have a foundation other than faith).
I do not understand this kind of objection. For those who hold faith as something one believes "without rational evidence", why would it be objectional to call it irrational. It is exactly what it is. Irrational does not mean stupid or dumb, it means without a rational (reasoned from evidence) basis for one's convictions. (Of course all superstitions, stupid ideas, and dumb notions are irrational as well.)
(Note, we do not call what one believes based on rational evidence, "faith," we call it knowledge. It is only called faith when what is believed is not based on reason from evidence.)
Hank