This would be great and all, but all parties who are in a position to choose to implement this kind of system or to keep the status quo are already motivated to keep (and expand) the existing systems, for any number of reasons. Everybody (except the end users) loves to keep that juicy metadata and incidental logs of everything.
More concerningly, if those parties were motivated to implement this system it would likely be because they've linked their fortunes to it and it is no longer a trustworthy system.