The article gets six paragraphs in before starting to discuss the actual legal issue. No bueno! Better summary: https://www.scotusblog.com/cases/landor-v-louisiana-departme...

Here’s the missing context. Congress has chosen to confer on prisoners certain freedom to practice their religion freely. For federal prisons, Congress can do this directly. But Congress cannot directly regulate the machinery of state government, so it can’t tell state prisons what to do, as the Supreme Court held in a 1997 case: https://en.wikipedia.org/wiki/City_of_Boerne_v._Flores. Note a key point here is that these rights are statutory in nature, and go beyond the protection for religious liberty required by the constitution.

To work around that, Congress has imposed certain requirements as a condition of accepting federal prison funds. Among other things, it requires states to answer prisoner lawsuits for violations of these requirements. This is a common approach: Congress can’t directly regulate the states, but it can bribe them to agree to do things. But if the state doesn’t follow the conditions, then the only thing Congress can do is withdraw the money.

What this case holds is that the state’s consent to these lawsuits does not mean suits can be filed directly against prison guards who work for the state. This makes sense. A company might have a contract with another company that requires employees to follow various data security practices. The company might have rules requiring employees to follow data security practices. But if an employee doesn’t follow those practices, the other company can’t sue the employee directly. The employee isn’t a party to the contract. Similarly, the state may agree to certain requirements in return for federal funds. Prison guards may have to follow state policies to implement those requirements. But the prison guard is not a party to the contract between the state and federal government and cannot be sued for its breach.