Interesting theory. Decades and centuries of advertising, long before our personal data was for sale or computers existed, would seem to indicate otherwise.
Still, assuming you're correct and these modern day ad companies can't survive in this new reality, I should care because...??? Why is it my responsibility to ensure these companies thrive? What other businesses out there are expecting me to "do my thing" so they can stay in business? Why does this burden rest on MY shoulders? Why are they entitled to my private data if I don't wish them to have it in the first place?
Just for the record, I've said MANY, MANY, MANY times (not that you would know of course) that if I hadn't gone into programming, I would have wanted to go into advertising (or psychology). I find the psychology of advertising fascinating. I love it. I'd hate to see that business go away, but I'm still not willing to give up my private information to prevent that from happening. If today's companies have forgotten how to market without private information, a new company will come along and figure it out. They may not be as profitable, but that's just one more thing in the "not my problem" bucket.