Bellingham helped defeat Borussia Dortmund in last night's Champions League final.
"I hope that the Ballon d'Or is tied not only to the victories and defeats of a player, but to his real efficacy within the team, how much he can improve the squad and those around him," Del Piero told Sky Italia, when discussing Bellingham, while at Wembley yesterday.
"We are coming off an era where Ronaldo and Messi dominated. That was often deserved, but not always, in some occasions others would've deserved to get the award.
"The Euros and the World Cup should only matter to a certain degree.
"They are big tournaments, but if the Ballon d'Or has to evaluate the full year, then it has to take other things into consideration too. There are many players who have incredible years. I want to be clear, sometimes we get confused and think the Ballon d'Or should go to absolutely the most talented player, but that's not what it is for."