That's not true, at all. Ashley Wagner won 12 Grand Prix medals, and 5 of those were gold medals. She won 1 silver and 2 bronze medals at Grand Prix Finals from 2012 to 2015. She won 4 Continents in 2012, and she won the silver medal at the 2016 World Championships.
Mirai won a lot of Grand Prix medals, and she was the Four Continents princess, too.Bradie Tennell has won 4 GP medals, since 2017, and a bronze at 4CC. Gracie Gold won 6 GP medals. While Karen Chen hasn't won GP medals, she's won medals at Challengers, as has Bradie. Mariah Bell has won 4 Grand Prix medals, as well as a number of medals at Challengers. There may be more examples, but it's too late for me to look up any more.
As I clarified in my post it wasn't my intention to say that US women haven't won anything, but since 2006 they have had little success in the major events (olympics, worlds, gp finals) after decades of consistent success in these competitions. So it's understandable in my mind that members of the fed/press are hyped at talents (in that case Lyu) that could bring them back to the past success.