I'm not convinced that's true, but let's assume it is for the sake of this discussion.
In that case, wouldn't a better approach be to mandate reasonable safeguards to protect against data breaches, and to penalise those who are seriously negligent in that respect?
Otherwise again I think you're aiming at the wrong target. Deleting stale data might have some marginal benefit in terms of privacy in the event of a breach, but the risk and consequences are surely much greater for the organisation that has only recent data but uses admin:admin for their root credentials. Meanwhile, the overheads of updating long-standing logging or backup systems where that older data might lurk to fully isolate everything could easily be among the highest practical costs for compliance, particularly for a lot of smaller organisations.
Peoples lives and most intimate details is going to be stored as bits. Get used to it.
Whether for targeting purpose (Facebook) or personal reasons (Strava). Whether stored on remote servers or home. It wont affect likeliness of data breaches. Focus on good software designs and let programmers design such systems in peace.
All this needed was fine for data breaches. Not the mess called GDPR.
Changing that is nontrivial, since it requires changing the behavior of everyone handling this data - so, something that can be done only by law. It will restrict Facebook, it will restrict Strava, it will restrict data stored on remote servers and home. While it won't affect likeliness of data breaches, it will affect the impact of data breaches - realistically speaking, many of the breached companies should not have had most or even all of that private data in the first place.
A data breach can't reveal information that you don't store; so a push to ensure that less companies are storing sensitive data, and those who do are storing less of it - that's something long overdue. GDPR is not designed to have people do X, Y and Z so that they can keep doing business as before; it's designed to ensure that many (most?) places where private data is used simply stop doing so.
So if the rationale for GDPR to reduce data breaches or to deny private data to future rouge govt, then it fails. Private data will still exist even if its not commercialzed. Its irrelevent who control it (user or company) as long as its connected to internet, there is risk of data breaches.
Unless you propose to go back to storing actual photos in actual albums. ITT im not sure.
But you can never guarantee that someone else won't do. The biggest issue to user's privacy has traditionally been data breaches. So even if you don't want to do something shady, a data loss might still be highly problematic for users.
I agree that IP addresses are unlikely to be the biggest concern here however.