There's more to it than that though. Defects in JIT logic can lead to nasty low-level bugs. Plain old interpreters, especially if written in a safe language, are unlikely to have similar issues. This is important when the input code is untrusted. JIT bugs are a major source of browser vulnerabilities.
JITs are an attack surface in that process. They are still restricted to things that process was already allowed to do, no matter how badly implemented the JIT is.
In this example usage, one would hope that authentication already happened before the JIT processed the command. So an authorized user can attack themselves is the only realistic risk, which is hardly significant