This comes up every time gdpr or ads are discussed. But it’s pretty simple I think: not enforcing privacy regulations forces site owners to break them.
The reason is that so long as some sites show tracking ads, the monetization possible by privacy-friendly ads is almost nothing.
The long term goal must be that no one cheats, so that ad the revenue from well-behaving advertising can go up.
Remember the consent dialogs aren’t ever asking permission to show ads.