It is not God who is narrow-minded, but those who do not accept His gospel. If God were to accept everyone regardless of whether they obey him, He would not be the just God that He is, and His words would mean nothing at all.
The Lord said, “If anyone loves Me, he will keep My word” (Jn 14:23; cf. 1 Jn 5:3). If someone claims to love God but refuses to obey Him, his claim is false.
God knows who truly loves Him (1 Cor 8:3). If a person never hears of the true gospel in his lifetime, it is God who will ultimately determine whether he was a true believer. But as for us who have already known the true gospel, it is our responsibility to accept and obey it.