In an open platofrm you will always be able to abuse in some form or another. But what will end is the platform abusing your data. And that is the point here. If I want to sell my data (or hand it to someone, whatever) I will be able to do this. But there won't be any central party selling my data. And that is all we can ask for.

To be more specific, I could make my data available only to those who I allowed to see it by including their public key in my list of authorised keys. Therefor no scraping.