Part of the trouble is the govt can't make up its mind. There've been at least 3 different sizes, shapes, and colors of dollar coins that they've pushed out over the last 30 years or so, plus the old "silver dollars."
When they released the 90's version, they passed a law saying all vending machines had to be modified to accept them, but I think that's been sunsetted. Somebody gave me one of the newest version a month ago, and I honestly thought they had slipped me a game room token until I looked at it under a magnifying glass.