Why is Ginger Rogers never compared to Hepburn, Davis, Crawford, or Stanwyck?

Even though she debuted around the same time as Katharine Hepburn, Bette Davis, Joan Crawford, and Barbara Stanwyck and was a major leading lady for several decades like the rest of them, she never gets compared to them acting wise. Why? Her career lasted just as long.

https://www.datalounge.com/thread/30437356-why-is-ginger-rogers-never-compared-to-hepburn-davis-crawford-or-stanwyck-