Pretty much everyone agrees that if companies like Google and Apple made local file sharing easy and cross-platform, all of us -- all of society -- would benefit.
However, these companies have financial incentives to do the opposite: they want users to do everything within tightly controlled platforms like Google Drive and iCloud, and they want to avoid commoditization at all costs. The last thing these companies want is for users to be able easily to transfer all their videos, music, photos, work files, contacts, calendar data, bookmarks, etc. from one platform to another.
The behavior of these companies is analogous to the behavor of AT&T at the beginning of the 20th century. AT&T had the largest telephone network with the most users, and smaller independent phone companies wanted to interconnect with it, but AT&T refused to do so, causing users to leave the smaller networks for AT&T's. Users of the smaller networks were unable to connect with users of the largest network. It wasn't until after the US federal government challenged AT&T for monopolistic behavior that this changed. In 1913, AT&T settled with the government in the "Kingsbury Committment," which required AT&T to allow non-competing independent telephone companies to interconnect with the AT&T network.[1]
I suspect the only way we can get easy and cross-platform data portability (local and otherwise) is via government intervention -- that is, if the government forces companies to do it for society's benefit (for example, by legally requiring compatibility with open data-sharing and app-interconnection standards), at the expense of user lock-in and corporate profits.
I agree with everything but your final two paragraphs; I suspect that a government-mandated solution would be horrible in all sorts of ways (poor security, a mandated backdoor &c.).
My hope is that the propellerheads in those companies are able to figure out a way to sneak this killer feature past their respective marketing people.
Government-mandated solutions can take many forms, some of which are less intrusive and/or more reasonable than others.
For example, if you live in the US, you are legally required by the government to drive on the right side of the road (to avoid the chaos of the past, when each US city and state had different driving rules), and you are also legally required to buy car insurance (to make sure irresponsible drivers who cause more accidents don't get a free ride from responsible drivers). I think most people would agree these are reasonable government solutions that are not too intrusive.
Perhaps it might be possible to come up with reasonable "rules of the road" that are not too intrusive and which the government can enforce so all of us -- all of society -- can easily share data between applications and platforms?
Apple and possibly, ironically enough, especially Microsoft both seems to be positioned to score here (create great solution, release specs, encourage adoption, be a hero).
Unfortunately I don't think they will. After Apple weaseled out of open sourcing Facetime and with Microsoft running their own cloud I won't bet much on it.
However, these companies have financial incentives to do the opposite: they want users to do everything within tightly controlled platforms like Google Drive and iCloud, and they want to avoid commoditization at all costs. The last thing these companies want is for users to be able easily to transfer all their videos, music, photos, work files, contacts, calendar data, bookmarks, etc. from one platform to another.
The behavior of these companies is analogous to the behavor of AT&T at the beginning of the 20th century. AT&T had the largest telephone network with the most users, and smaller independent phone companies wanted to interconnect with it, but AT&T refused to do so, causing users to leave the smaller networks for AT&T's. Users of the smaller networks were unable to connect with users of the largest network. It wasn't until after the US federal government challenged AT&T for monopolistic behavior that this changed. In 1913, AT&T settled with the government in the "Kingsbury Committment," which required AT&T to allow non-competing independent telephone companies to interconnect with the AT&T network.[1]
I suspect the only way we can get easy and cross-platform data portability (local and otherwise) is via government intervention -- that is, if the government forces companies to do it for society's benefit (for example, by legally requiring compatibility with open data-sharing and app-interconnection standards), at the expense of user lock-in and corporate profits.
[1] https://en.wikipedia.org/wiki/Kingsbury_Commitment