That's the worst thing about Google Ads. Google keeps an absurd amount of the money, and they punish your users. And, of course, ads in general became so abusive and intrusive that everyone uses an ad blocker, making ads less effective as a revenue source.

But, I don't see how a static HTML site could be a struggle to keep running. It costs almost nothing to host something like that, even with a lot of traffic. I guess if one wanted to make a living off of it, it'd be a struggle.