Currently, there is not a way to filter features with the status "Will Not Implement" on the releases road map. I have no way to hide them apart from deleting them all together. It's cluttering the report.
Thank you for your idea. One way to handle this now is to manually remove the features that you no longer want to show up on the releases roadmap. When you hover over the feature name you will see an X to remove the feature.
Given this capability, we are unlikely to implement this idea at this time. We hope you can understand.