In 99.9% of cases defining legitimate use is simple. There should be legal consequences for data sharing that is not actual legitimate use. I see companies making absurd claims about what consent based on "legitimate interest" can mean. No, sharing data with advertising "partners" is not based on any legitimate interest. If these companies were getting some strong fines for illegal stuff like this, then they would cut the bs.
I think banned it a bit too strong. However there needs to be strong regulations on what can be shared.
If I go to an ER in a different area (read different medical system) I want my doctor to share personal data. I don't want my doctor to share my personal data with a random doctor in the same medical system unless that other doctor is an expert being consulted on something about me. (that is just being a doctor doesn't give you access to my private information, it needs to be on a need to know).
The above is the obvious case. There are likely other cases that are not obvious where after looking closely private information should be shared. Advertisement is never one of those reasons though, and analytics is only a reason if they anonymize the data with prison terms for mistakes.
Indiscriminate sharing of personal data IS banned under the GDPR.
If you collect personal data, you must only collect it for the stated purpose and can't sell or share it for any other reason.
I continue to be astounded at the ignorance some people have of the GDPR; a vital privacy law and one that is fundamental to modern data use and respect for the customer.
Nah. Personal data sharing needs to be banned. It's the right way forward.