And for you, who say that Riot should be more lenient for pro players flamign others, think a bit. For pro-players, game is job. Would you start insulting and so on your own customers when you're working? Eventually you'll be fired, or in this case, permanently banned, from your job, if you continue being disrespectful for your customers / viewers etc.
These 2 players were in tribunal multiple times, and also banned many times before permanent bans. They knew they'd be banned sooner or later, but didn't fix their behavior, despite many warnings.