The gap between a declared policy and an enforceable right was filled, once, and narrowly.
In 1990 the Supreme Court held in Employment Division v. Smith that a neutral, generally applicable criminal law does not offend the free exercise clause even where it burdens a religion. The case concerned two members of the Native American Church denied unemployment benefits after being dismissed for peyote use, and the decision left sacramental peyote unprotected by the constitution.
Congress answered twice. The Religious Freedom Restoration Act of 1993 restored a compelling interest test against federal action generally. Then the American Indian Religious Freedom Act Amendments of 1994 addressed the specific practice: the use, possession or transportation of peyote by an Indian for bona fide traditional ceremonial purposes in connection with the practice of a traditional Indian religion is lawful, and shall not be prohibited by the United States or any state, and no Indian shall be penalised or discriminated against on that basis. Unlike the 1978 Act, that provision is a rule a court can apply.
The rest of the ground has been covered piecemeal and unevenly since, by the graves protection statute of 1990, by executive orders on sacred sites and eagle feathers, and by consultation requirements in land management law. The Act remains what it says it is, a statement of policy, and the litigation over sites continues under other headings.