Maybe so. We use whiteboarding as a jumping off point for discussion, not to implement trees or graph traversals. It is usually apparent within a few minutes if the candidate knows their stuff, and we move deeper. Additionally, there is always going to be an onboarding period, where the new hire is learning how our team does things. We spend a lot of time communicating and drawing out ideas on whiteboards. We need to see if you can communicate clearly. Saying "naa, I don't whiteboard" is NOT a good start. In all likelihood this person would be a bad fit.