> neighbors doing something legal

The question is about doing something illegal, such as removing a covenant that was involved in a sale when reselling? If it is something that could have been objected to by the original seller (they would have had standing to sue) and they have not agreed to change the covenant (because they are dead), it seems as if anyone affected should be able to sue.

The breaking of the covenant is what is being sued over.

> Presuming the land is zoned for a datacenter, the datacenter is allowed to do datacenter things.

If my house is zoned for a possible datacenter, that doesn't mean that anyone can build a datacenter there - it is still my house. If there is a covenant that says that the land will be a park, that's the "zoning" by the seller being stricter than local zoning, which means that it also conforms to local zoning.

The zoning doesn't say "The land must be a datacenter."

edit: It would be bizarre if we can sue over terms of service as if they constitute law, but we couldn't sue over terms of sale. I can sue Facebook if they allow another user to violate their terms of service.

> If it is something that could have been objected to by the original seller (they would have had standing to sue) and they have not agreed to change the covenant (because they are dead), it seems as if anyone affected should be able to sue.

They don’t because it’s a private agreement, so only the involved parties can sue. In this case, if the original seller died then standing to sue would be inherited (I believe). If the inheritor doesn’t care, then neither does the government.

There’s also a bunch of weird edges. Like if the land just isn’t usable as a park because it’s too out of the way to be worth maintenance or building it would be insane because it’s a literal swamp, what is the city supposed to do with that? Own it and just do nothing with it in perpetuity?

> If there is a covenant that says that the land will be a park, that's the "zoning" by the seller being stricter than local zoning, which means that it also conforms to local zoning.

Sellers don’t get to do any zoning, the city does. You can add a covenant that says a single family home in San Francisco can only be used for fracking, despite the fact that there’s no oil and zoning wouldn’t allow it.

> I can sue Facebook if they allow another user to violate their terms of service.

No, you can’t. Or rather, you can file it, but it will be tossed out immediately. There is no tort for failing to enforce your own ToS. You might be able to sue Facebook for negligently failing to stop a user from breaking an actual law.

It’s against Facebook ToS to use a name other than your legal name on your account. How confident are you that you could win a lawsuit against Facebook because Post Malone’s account isn’t named “Austin Post”?