Weirdly enough, the people who were most vocal about this so called "Free Market" were the people who tried to defend their ability to make money from things that can be copied infinitely with almost zero overhead.
This isn't an opinion on whether or not digital media should be free, it's a statement about digital media being completely incompatible with outdated economic theories.
The person you're replying to may actually believe that his personal information should be worth $0. The only reason it's not is because it can be used for targeted advertising and a bunch of even more horribly dystopian purposes.
So, the fact is you're both correct. Personal data should be worthless (in fact, it should be only available with the permission of the "person") if not for bad actors profiting from the purchase and sale of this data.
The broken economic theories of free market economics state that digital media should be worthless, except that current laws and regulations extend out-dated intellectual property laws to protect incumbent distributors and rights holders (this only rarely actually protects the creators of the media). The idealistic goal of the creators profiting from their creations has been corrupted beyond recognition.
Basically, the things you both are discussing are both nuanced and broken. They exist outside of the context you're putting them in.