It depends. I make it very clear as to what kind of board you are purchasing, which dictates whether you can use utensils on it or not.

Charcuterie Boards - I do not recommend using utensils on the resin (hard plastic) portion of charcuteries boards. This is a safety issue as using a knife on the resin can chip it and you could ingest it, which is not good. It would also scratch the resin. If you have a board with wood and resin, feel free to use utensils on the wood portion.

Serving Boards - You can use utensils on a Serving Board. However, pay attention to the included note for your board as I do not recommend cutting certain things (i.e. juicy foods) on certain species of wood, mainly pourous species like red oak.

Cutting Boards - Yes. Please do. That is the point.