haha nothing wrong with fashion.
discussion point: if a workplace culture condones the use of designer tie-clips, this may allude to the point that business-attire could be a factor on the judgement of colleauges. (excluding colleagues who deal with external clients etc)
May not be an issue in your space as mentioned but could be in other places.
Have always worn company issued uniforms for both Site & office along so never had the issue.
However where ones uniform is prescribed, the stand-out factor is usually the flashiest watch.