I doubt the meekness will ever change. This is the staple of most isekai and fantasy world japanese stories. He'll always be a polite humble OP gentleman introducing them to the wonders of modern food and toiletries. Soon he'll serve them sushi, soy sauce, ramen as well dig up a hot spring and have them enjoy sake (this is all just assumptions since I've not read the WN but I can bet it will happen).