How Do Sites Get a Very High DR With No Traffic?

Hi guys, complete SEO noob here.

I've been learning SEO for about the past 2 months, in this time I have become very accustomed to the Ahrefs tool. I know that the Domain Rank from Ahrefs is completely proprietary from their end and so needs to be taken with a pinch of salt.

That being said, I very often come across websites that have really great Domain Ranks (Upwards of 70, one had a DR of 85). Yet their organic traffic is listed as '<1' could anyone give me an understanding as to how this happens, please? Is it a PBN thing?

Any reason would be greatly appreciated, Thanks!