There is a huge difference between providing a service with adverts to pay for it, and what almost all lyric sites are. They don't just put up ads and the related opportunities for adtech to stalk us in order to pay for the server and bandwidth: they spend time and money (SEO, sometimes more active advertising themselves) seeking out more and more visits to extract more revenue from that stalking and advertising relationship. And the have few standards on the sort of 3rd parties they deal with: last time I found myself on such a site and some things got through my blocking, the ads shown wouldn't have looked out of place on a porn site.

Selling ad impressions and stalking opportunities is the point of those sites, offering lyrics is just a way to do that.