Might not be the giants of today. I think people begin to realize how much power they are handing to these companies whose interests are not at all aligned. If you had a car and wanted to drive North, would you take the back seat and give the wheel to a random person who makes no mystery of wanting to drive South ? This is what people have done with Facebook

Decentralized is a complex word - decentralized yes, in the sense of a "platform with a governance structure which aligns the interest of the operators and the data owners"