It's a myth that the Brits only preserve their older buildings. We have *loads* of those, so we tend to preserve only those with unique elements or important historical ties. (For example, there's no shortage of Georgian and Victorian-era housing.)
1920s is still "old" for a Brit; like most cultures, we use living memory and lifespan as references for this concept. Plenty of buildings from the inter-war years have gained Listed preservation status. These are mostly one-off buildings of genuine architectural merit.
The difference between the Old and New Worlds is that we don't consider "old" to be remarkable or special in and of itself, any more than Americans gaze upon skyscrapers or air-conditioned homes with awe and wonder.
The rise of the preservation and heritage movements in the UK grew out of the destruction of the original Euston railway station in London and its replacement by the grotty little box which still stands there today (and is now being considered for demolition). This triggered the creation of preservation movements which were directly responsible for the survival of St. Pancras railway station in London, now refurbished and adapted as the terminus for the Eurostar services to mainland Europe.
My personal view is that anything proposed for formal preservation should be bought from its owner(s) for the price they paid for it. If nobody is willing to stump up the cash to do this, it's clear that the building isn't *that* well-loved, so let it go. We have the technology to record any building or relic for posterity should we need to demolish it, so we wouldn't be losing all trace of the structure forever.
With regard to Steve Jobs' problem: I agree with Jobs. It's an old, impractical building with little architectural value. It would be uneconomic to restore as few people would be willing to live in such a building today. (No decent insulation; no modern electrical system; far bigger than it needs to be for the smaller families we have today, and so on.) It's old, but old doesn't automatically imply *worth preserving*. Let it go.