After the last talk he had with Riff, Tony hoped that he was going to remember that he was allowed to show his emotions and that he shouldn't hide them just because he thought that showing anyone his emotions was showing weakness when it wasn't showing weakness,it was showing he was human with feelings just like everyone else. Humans showed emotions all the time and Riff may be a gang leader but he was firstly a human being and he had emotions like everyone else has emotions. Riff needed to understand that but his pride and everything else got in the way of Riff ever having a chance to understand.
But at least Tony was there to help him to try to understand that he was only human and was allowed to show those emotions just like every human being. Even the strongest of people have their moments where they show emotion and that's totally normal. All humans showed emotions whenever they need to show emotions even though they are strong and all that. Human beings have emotions no matter what it is and if they're strong,emotions still have to be part of life. That's just how it goes and will always be that way. Riff Lorton was no exception even though he'd never admit it but he was only human with human emotions. He may not like showing emotion but he still has them. He'll have emotions like everyone else until the end. He may not like showing emotion but he has them anyway and there's nothing he could do to change that.