It is not only about Ronaldo. Juventus knows the potential business of cryptocurrency in sports. And It is not the first time, we have seen Ronaldinho released his coins. And maybe there are more parties from the sports sector trying to launch their crypto coins in the near future. I think it is no problem, as long as the coins are valuable.  
 
Overtake Bitcoin? Lol. I don't think any altcoins can overtake bitcoin.