I have clicked the unsubscribe link at least 20 times, they keep sending me multiple newsletters every day.

I have emailed their customer service multiple times, they never got back to me.

I have opened a complaint wih ACMA: https://www.acma.gov.au/spam-and-telemarketing - hopefully it will have the desired effect.

I am an EU Citizen and I considered also sending a GDPR request, but due to the fact that I no longer reside in the EU, I think the EU privacy laws don't apply to me.

Anyway, my advice is: avoid subscribing to Te Futurist if you don't like spam!