Mashing up data has its consequences. I believe that's why we have to see that,Deep data protection is taken into consideration when building robust database to hold this data.
It would preferably be nice for security to be linked to certain policies that can be granted to rows. This would therefore limited applications being the gateway to insecurity.
But notwithstanding for authenitcation and authorisation to take place and followed by a single-sign-on process. Id's would still be in use. Identifying,recognising and accepting has lots to play.....I believe it would be nice to have data stored in another medium--but what would that be is the question.