Miles redemption for international flights, what am I missing?

Hello - happy to have some advice. Was hoping to fly from Munich to Texas this year to visit family and have a ton of miles to redeem. However when I look, once I consider paying taxes and fees, the redeemed flight is nearly the same as just paying out of pocket. What gives? What’s the point of miles?

ETA: I don’t have most of the miles converted to Lufthansa yet, they are Amex miles. But Lufthansa is my home airline/hub, so it’s the likely move I guess. The other issue is, with their website I can’t see how many miles are needed for a certain ticket or class because I don’t currently have enough miles. Was hoping to get a peek before converting. If anyone has any tips there, I’d be grateful.