Riot games recently blocked access of thousands of games from Iran & Syria. Claiming that due to U.S sanctions it is forbidden to have players from these countries? 

This does not appear to be appropriate at all. These are teenagers that are just playing a game; how playing a game might be considered as trading with a country?

I hope riot games recognizes that treating players like this, like they have done something wrong only because they're born from certain countries, makes them only feel bad about themselves and affects their minds like they have been abomination in this world.

They're just children that want to be part of an entertainment, how is that even related to political problems and trading with U.S citizens.