What are rights, considered not as a moral or legal category but as a description of how people act?
This definition of government would seem to include any criminal organization that successfully taxes businesses or enforces a monopoly on some use of its territory, which I suppose means there would currently be thousands of governments in existence, with much overlap in territory. Is this intentional?
If I understand this correctly, the key idea is that Schelling points influence one's predictions of others, viz that is it reasonable to believe that another will carry out a threat in defense of a salient status quo (eg, that you will go to great lengths to enforce your property rights), and not to believe that they will do so to promote some non-salient outcome (eg, that he will bear large costs if you don’t allow him to violate them).
Not sure. True, the salience of a would-be outcome /can/ ground expectations about the actions of others, but such expectations can be defeated. Threats are a case in point. By definition, a (sincere) threat is a commitment to perform a certain non-maximizing action should the other person "misbehave"—eg, your threat to call in the lawyers if he does not take back his trash. This means (i) that your neighbor already has reason to believe that you will /not/ really do so. For it is cheaper for you simply to pay him $5. He expects that you will be "rational" (= do whatever maximizes your expected-utility). Still, suppose it is maximizing for you to be the sort of person who /would/ call in the lawyers, since, if you were like that, then he might be deterred. Even so, (ii) your neighbor might still have reason to believe that you are /not/ really like this. For the degree of non-maximization involved in carrying out such a threat may exceed the degree of non-maximization of not making it in the first place—for example, if you threatened to blow both of you up if he did not take back his trash, or (more plausibly) if calling in the lawyers approached this level of cost. He expects that, if you are going to be "rationally irrational", then you will do this in a "rational" way, and, in this case, that would be by not making any such over-the-top threat, even if it would work (if only it could be believed).
Either way, it may not be reasonable to believe some threat, even if it is focused on a Schelling point. This will limit what costs you can accept in order to deter you neighbor (if he will be deterred only threats costly to you), and give him some scope to counter-threaten you (if you will be deterred from your initial policy by threats not-so-costly to him).
I wonder if a more precise purely empirical description of “rights” in a society S at a time T would simply be the psychological question of what its members descriptively believe about the moral and legal constellation of “rights” questions. This inquiry is not at all normative—it is a purely empirical question of what certain people believe at a time. It is admittedly less tractable than an approach predicated on something like “Schelling points” but I bet it would more accurately model the descriptive question we’re trying to figure out.
If rights are just what others expect you to be "successfully committed to defend" then they aren't rights as we understand them, just recognitions of power.
Say we have a bully and a wimp. The bully is succesfully committed to defending his right to take the wimp's lunch money and the wimp is unwilling to infringe on that right, so he surrenders his money to the bully. But is the will of the stronger a right if it is an expectation backed by force? Is the only thing that prevents the bully's will from becoming a right a stronger power, like the school principal? Or is there a deeper principle here?
I'm pretty satisfied with my account of rights here: https://neonomos.substack.com/p/there-are-no-natural-rights-without. Rights derive from those principles that reasonable people would agree to behind a veil of ignorance. Those principles themselves are subject to a schelling point, since they are based on publicly shared perceptions of what free people would agree to.
So I partly agree with your account of rights, as they are based on public perceptions, but there are certaintly other features which provide rights with a moral element.