The only time I've used whiteboards in my job is either when I need to hash out a solution or approach with my coworkers, because I'm confused or don't understand the problem, or when I need to understand high-level architecture for a system. It's a tool for clearing one's thoughts and for getting a team "on the same page".
If you're hiring someone to code-monkey a bunch of JIRA bugs, then whiteboarding might not be a relevant test for them. If you are hiring someone to build out new features efficiently or redesign architecture, then whiteboarding may be useful for having them describe at a high-level how they would solve problems. In both cases, writing syntactically flawless solutions on a whiteboard is a waste of time for both the interviewer and interviewee.