> But this aggregation is stale and when xyz is patched and months have passed you just have gigs of data that has gone bad, and just like rotten fruit that wont sell for much.
Not really. First off, I would imagine it would be possible to script finding people's servers and scraping it for data. Ultimately these servers will have to be hosted somewhere and systems like masscan make it easy to rapidly find servers hosting software that you can exploit. What's more, now the person is responsible for this risk level. Sure, a couple of experienced sysadmins like myself or you would know how to secure our data and make the server difficult to scan or probe, and difficult to access in the worst case, but how many users are actually going to be able to put in the time to learn system administration, to ensure that a server they are hosting is secure? It takes a lot of work, especially if you do not know the first thing about computers.
The end result of this will drive the introduction of businesses whose responsibility is to host these servers, and now you are back where you started, except worse! I can reasonably assume that just because my welfare data has been breached, that does not mean that they could access my medical records. Now however, that is not the case!
Secondly, even data that you would assume is stale, can be important and viable. Old phone numbers, for example, are still valuable as they can be used to construct a history for the given person, and often identity confirmation procedures require listing old information along with new information (A friend recently had to list places they had lived at to confirm their identity, which meant that they were unable to confirm because it was requesting a full list of addresses they had lived before they were ten (!)). Databases like Medical Records or your National Insurance Number do not tend to lose their value just because they aren't from this year data. Often old security questions and passwords are just as valuable as new ones, old information can be used to construct a 'good enough' profile and either used to sniff out newer more viable information, or used to aid the rapid generation of possible and likely passwords, among other things.