>Most of the value in these networks is in "network effect", i. e. it's usefulness is a function of the number of other people using it.
No, the only reason "network effects" matter on something that is useful specifically because it makes the transfer of information instantaneous and fluid is because we have artificial barriers (CFAA/IP) in place to keep that data stuck with one vendor.
Without this, the number of people using Facebook to access Person Data would be transparent to the average user, much like the number of people using Chrome or Firefox to access hypertext. And much like Chrome and Firefox, the switching penalty would be reasonably surmountable for most users. It's the difference between learning a new interface to the data (as in switching from Chrome) and being cut off from the data completely (as in switching from Facebook).
SaaS sites have network effects specifically because we (accidentally) legislated those effects into existence. There are no physical barriers locking people in -- the "wall" of this garden is entirely artificial.
>"Walled Gardens" have nothing to do with IP laws.
>If the user grants you permission, IP laws cannot be used to stop you.
This is 1000% false. IP laws absolutely CAN and HAVE been used to stop people from accessing online resources, even to get information that the user has authorized the data gatherer to collect. That's because when you download a page from one of the major tech services, you're not just downloading the user's copyrighted content to which the host has a license, you're also downloading the host's copyrighted code and parsing through it to extract the user's requested data.
That's been interpreted to be an infringement under the Copyright Act on multiple occasions: Ticketmaster v. RMG, Facebook v. Power Ventures, Perfect 10 v. Amazon (in which the judges ruled Google's use fair on appeal, because it was Google), and others. While you may be able to argue there's an implied license if the robots.txt is blank, that is only going to last you through the first notification that the host doesn't like your activity, which is not necessarily formal (cf. Craigslist v. 3Taps), which would matter both for CFAA and copyright purposes. It's not an issue limited exclusively to something sneaky done by Power.
Even if IP law itself was irrelevant (and it's not), there would be a lot of work to do here just in fixing up the laws around network access and blocking onerous Terms of Use.
>it's just not true that there are millions of people waiting to migrate away from Facebook if only they could transfer their photo library.
Whether you believe someone could do a better job than Facebook or not, surely you don't believe it should be, for all practical intents and purposes, illegal for them to attempt to do so.
>That people do not do so has nothing to do with your conspiracy theories.
Please try to start this type of service and get back to me about "conspiracy theories" after a C&D destroys your business, as it has hundreds of others, including mine.
Not to be rude, but you clearly have never dealt with this in a serious manner. Please be more careful before you go around making assumptions and dismissing the perspective of those with direct experience.