Very interesting, someone did that to a project of mine 10 years ago.

They registered $my_projectname.org and loaded my site in a full screen iframe with ads over it.

Traffic was up to 500 users per day that I was never able to monetise, I doubt they got a lot from their iframe either.

But they beat me and some other similar sites on SEO very hard, very fast and I never quite figured out how.

I ended up serving a white page to that referer.