The US has lots of talented young girls as well, but in view of the rise and fall of Nagasu and Zhang, it's best to wait until very young skaters pass through the ravages of the puberty bug before declaring them stars.
But Radionova is a star, and she will be in history of FS, even if Triglav Trophy-2013 will be her last competition.
More mature age also gives no warranty. Silver medalist of Worlds Leonova significantly degraded at age 22, and nobody knows will she restore or not.
Asada had two poor seasons after Olympics-2010.
And so on.
So let us enjoy skating of all skaters who skate well now. Even if their future is not guaranteed (in fact future of any skater is not guaranteed).