Health- I totally agree with you, that’s why Dor Yeshorim works the way it does. Even being a carrier is a stigma when there is nothing to worry about if the other partner is not a carrier.
The reason why we are behind the goyim is because of the modest way we go about finding a spouse. If a guy is given five names and information of potential dates and one of them has a “stigma”, she will immediately be eliminated.
If the goyim would date the same way as us there would be the same stigmas.