As a person, I believe that you should be able to decide how much information you give away and your experience shouldn't change vastly if you keep it all to yourself.
As a marketer, that's an absolute nightmare.
So I enjoyed the handling of a no-data scenario in this article (via @andrewallsop) by Michael Taylor who writes:
"if I was put in charge of growth for an Ecommerce company, how would I run marketing without user data? On day one of the new job, the UN declares all user-level tracking is banned, under the Universal Data Protection Regulation (UDPR). Only aggregated data (minimum cohort size: 30 people) is allowed, or you get fined 10% of revenue. How would I still do my job?"
In it, Michael covers a 5+ week series of activities he would undertake to replace the current data-collection and heavy practices we all use as marketers.
This is a brilliant read.