It is up to Facebook to use both technical means and enforceable contract law to draw lines around how their service can be used, the same way it is up to any of us to do the same with services we stand up on the Internet.
There are limits to both tools, and legislatures can enact new restrictions in response to public demand. But none of that is in play in this story.
If the argument upthread was "we should demand laws that prevent Facebook from locking out extensions to their platform", I wouldn't have a rebuttal (I might or might not support those restrictions). But the sarcastic dunk that was actually made, that it was somehow ridiculous that Facebook would have some say over the terms of how their platform was used, was weird and worth commenting on. It's not only not ridiculous, but actually the world as it exists today.
>[they said] it was somehow ridiculous that Facebook would have some say over the terms of how their platform was used
It's less about FB's right to set boundaries, and more about what FB does when they feel the boundaries have been violated. In this case, they've perma-banned the guy and initiated threatening legal action. That action's extreme demands are NOT in FB's TOS, and reflect on FB's attitude of entitlement.
One argument against this is that FB is just doing the "standard legal thing" of demanding everything up-front, and then negotiating. That is true, but I don't think that just because every lawyer tries to bully their clients enemy means they should. And in this case FB is Goliath, swinging hard and fast at David.
There are limits to both tools, and legislatures can enact new restrictions in response to public demand. But none of that is in play in this story.
If the argument upthread was "we should demand laws that prevent Facebook from locking out extensions to their platform", I wouldn't have a rebuttal (I might or might not support those restrictions). But the sarcastic dunk that was actually made, that it was somehow ridiculous that Facebook would have some say over the terms of how their platform was used, was weird and worth commenting on. It's not only not ridiculous, but actually the world as it exists today.