A) Facebook is free, but pay €9.99/mo. if you don't want ads or ad tracking
B) Facebook costs €9.99/mo., but will enable a free tier if you'll accept ads/tracking
Option A seems to provoke outrage (like this article/lawsuit), while option B seems... perfectly reasonable. Even though they're the same thing.
People just hate having stuff taken away from them. They feel that Facebook ought to be free because it always has been, the same way a lot of people are still bothered by checked baggage fees on airlines because checked baggage had been included for decades.
But legally, there's really no difference. And companies have to make money somehow. It would be fascinating if EU regulations actually led to the birth of an alternate, optional internet model where you paid $40/mo. extra to your ISP that got sent to Meta/Google/etc. according to your browsing proportions and resulted in no ads and no ad tracking across Facebook, Instagram, YouTube, AdSense, etc.