Having ancestors who practiced Judaism does not make their descendants "Jews", no more than having ancestors who worshiped trees makes anyone a Druid.
Plenty of people have converted to Judaism, and they are Jews. People who renounce or don't practice Judaism aren't.
It was a Jew-hating German who popularized the concept of Jews as a "race" and brought the term "antisemitism" into widespread use.
https://www.jewishvirtuallibrary.org/wilhelm-marr
Thank you.
