> not staying anywhere? Or does Himachal also have laws like this?

Non-locals are allowed to stay anywhere in HP, but zoning is strictly enforced so you aren't going to find some hotel or B&B in the middle of nowhere without it being zoned as non-agricultural land.

This helps limit tourism to a handful of urban hubs, which helps limit overtourism to a handful of areas that have essentially been written off.

That said, significant swathes of Himachal fall within the Protexted Area Permit and outsiders need permission from the Home Ministry for extended stays, and often get stopped by police or ITBP for checkings (unsurprising given that we neighbor Tibet and plenty of communities have ethnic ties with residents of Ngari).

> I doubt this has been given judicial review at the High Court/Supreme Court level

Tribal Councils and Panchayats in Meghalaya are allowed to use customary law to limit outsiders, and this has been adjudicated by the Meghalaya HC as well.

Meghalaya also falls under the Sixth Schedule which was explicitly made to ensure that tribal areas aren't inundated by more numerous outside ethnic groups.