Welcome to the forum! We should never be ashamed of our faith in Jesus Christ. It think it depends on each person and why they are choosing to, or choosing not to, wear our ashes publicly.
Are you doing it out of pride? Then maybe sporting the ashes is not suggested.
Are you not publicly wearing ashes out of shame or fear? Then maybe you should keep it visible.
Here is a story about a time when I decided to wear the ashes publicly. It could be the witness someone else needed in their life.