It is true that the personalities of certain individuals can influence others to take a decision ,either in investments,choice of dresses,etc.The striker's involvement in cryptocurrency will sure have a positive influence on cryptocurrency especially his fans.
Didier is a footballer who opinion to me does not matter in the world of finance or investment which bitcoin operates. The reasons why most of the products they serve as brand ambassadors for are public goods that one does not need any special skill sets or take certain significant risk in other to patronise but the same thing cannot be said about bitcoin. So far Didier won't be responsible for the loss I make by investing in crypto or be the determining factor in me making profit, then his opinion of face in postals does not matter.