I have had great experiences getting glasses from Jins, which has locations in the US and in Asia.
I don’t know about Jins, but I’ve owners many paid of of Zoff (the other big Japanese maker) and they’ve all been made in Japan or Korea. There’s also a ton of small brands in Japan still. And it’s kind of interesting that virtually all Japanese eyeglasses are made in one city (Sabae).
Likely to be a case of ethical concerns. It's too often that these companies are using un-ethical labor sourcing in third-world countries, and I am guessing OP isn't interested in supporting them.
Have you looked into labor conditions in the US recently?