I am all for reigning in Facebook, Google and the likes. They have become too powerful in the world, and as corporations are not democracies, this automatically subverts democracy and will lead to bad outcomes (we're already seeing that).
But actions will be ineffective in the long run, and even cause more collateral damage, if linking and reusing information would become (too) regulated.
Instead, the actual issue is that customers are paying for products with their personal data, which leads to targeted advertisements, incentives to generate clicks, algorithms that amplify bad emotions and fake news etc. etc. Most of the customers think they do so willingly, but are not aware of the devastating consequences for society as a whole, and for them personally if they have a bit of bad luck.
That is the issue that should be resolved. Advertisement must be limited by law, in one form of the other. Even those that have a religious belief in the sanctity of free markets and expression, will have to see sooner or later that the freedom they are trying to protect, will be wiped away be the consequences of this.
Free services with hidden cost should be banned, and the whole business model that underpins Facebook, Google and some others must go away.
I guess, Facebook and Google, now fighting these illogical laws, would be very happy if the counter forces would be only this, instead of what is actually needed, the end of a large part of their business model.