This is actually one of those instances where I'm not sure how open sourcing a product would make it freer. Don't cloud providers make their dime by what-they-have, i.e. your data, instead of what-they-do (i.e., the source code)? As far as I understand, it's the prices of ingress vs egress that act as the mortar in these particular gardens.

Like if Facebook went full open-source... how does that help, if they retain sole custodianship of my data?