I understand that laws can have an immense impact. In fact, I believe that our bad network access and copyright laws have enabled things like Facebook to become scary data-hoarding monopolies in the first place.
Without the CFAA, without improper application of trespass to chattels, without improper application of the Copyright Act to RAM copies of pages that exist for mere microseconds, and without considering exploitative browsewrap "agreements" legally binding, Facebook (and most other "walled gardens" that effectively downgrade the WWW into just another technical curiosity in content delivery instead of an independent, open, and free publishing platform) could relatively easily be harvested and reduced to something like the decentralized protocol described above, which would greatly enhance individual privacy and control moving forward. But I digress.
Uber and AirBnb have physical-world touchpoints that are easy to police using our existing police and justice infrastructure. You're driving a car with revoked registration or renting out a unit in an area not zoned for short-term rentals and/or without the proper licenses. These are straightforward violations that are trivially observable, relatively simple to prove beyond a reasonable doubt in a court of law and reasonably within a jury's comprehension and familiarity, and we can send a real guy with a gun to come and haul you off to jail if you break these rules.
All-digital conduct, like storing too much metadata, is much harder to detect, curb, and assign accountability for. And even if Facebook itself is stopped from making the correlations or compilations outlined by such a law, nothing can stop under-the-radar third-party scrapers or special-privilege actors like intelligence agencies from combining the data exposed to Facebook and ultimately achieving the same end: an uber-effective mass surveillance system capable of identifying anyone, anywhere (potentially even digitally) with nothing more than a semi-decent picture of their face.