Zionism only started in the last 150 years. It's a structured belief with its own tenants. There's also anti-Zionism, which was a competing belief that died about 100 years ago. Read about Baron Maurice de Hirsch, an anti-zionist who sponsored emigration for thousands of Jewish people to Argentina, including my ancestors. At the time, the anti-zionist belief was that the old world was too corrupted against Jewish people, and that Jewish people needed to settle in the new world for their religious freedom.

Instead, Theodore Herzls delusions won out, and now we have the Zionism issue.

Sorry that your relatives use Zionism as a dog whistle, but that's on them for misusing the terminology.