I'm guessing she meant a female cyclist back then was unusual maybe?
For me though a grandparent born that long ago is unusual - just checked my own tree, and 1870s births are great, great grandparents for me in the main and great grandparents on the other - none of my grandparents were born out of the 20th century (and half of the great grandparents were also born 20th century)
But if you yourself are also older stands to reason your grandparents, on average, also will be