I think the biggest factor was that World War II came along and knocked the whole European figure skating program for a loop. Especially in men's. In the 18 years between the two world wars Austrian men won a total of 31 World medals. When skating resumed after the war, from 1948 to 1959 U.S. men won 12 straight world championships, facing little competition from Europe.
Beatrix Schuba was a great champion, though. Probably the greatest figure skater of all time.