Trash talking and even playful banter by itself are fine but even they have their limits, and no I'm not just talking about things like death threats or racial slurs. Cross that line or take it too far and you can expect to be held accountable for it, even in pro sports. At that point you're no longer trash talking but just talking like trash. There's nothing wrong with expecting or requiring at least some level of maturity and sportsmanship out of players. and the sad truth is that players who become known for behavioral issues can eventually have that overshadow their skill. Pro LoL player Dardoch is one such example, as though he's skilled at the game he's been on multiple teams due in part to being difficult to work with behavior wise.
When it comes to the mute button while I do agree that people should use it when need be overall it is meant to be a band-aid solution at most, not a get out of jail free card or a catch-all excuse. As for the sensitivity argument, From Ulanopo’s Knowledge Base:
People who report are simply being oversensitive. The mute button exists for a reason.
Let’s start with the Riot quote on this (link (http://forums.na.leagueoflegends.com/board/showthread.php?p=30696571#post30696571)):
Why is verbal abuse punishable if there is a mute button/language filter?
Players shouldn’t need to rely on features like the mute button or language filter to engage with other players in positive ways. When a player verbally abuses another player and forces him to use the mute button, they have already created a negative experience for that player.
Simply put, Riot says no. You can scream and cry all you want, but it is their house and their rules.
With that out of the way, I think the topic deserves some further discussion. The theory is that, if people resolved to care less, then they would be happier. I often refer to this as ”Argument from Stoicism” and I think it is a fairly weak philosophy because it places the burden on the person being expected to endure the behavior rather than the person exhibiting the behavior. “You should be able to handle it” is just a flimsy excuse for being a bully or a jerk. I have to be the bigger man so that you can do whatever you want? That hardly seems fair.
There is also the issue of how I spend my limited free time. Like most people, I am constantly required to make value judgments between the different forms of entertainment that are available to me and, let's be honest, we live in an age of nearly limitless entertainment options. If I'm having a bad day in League, I can just fire up Steam and play a whole bunch of games that don't require me to put up with someone's BS.
This is not an issue of weakness or thin-skin; it's a question of choosing activities that don't leave me feeling frustrated and angry. Too many of those experiences and I'll just find something else to do. Riot knows this.
Also, from Riot Tantram:
People might be used to feeling powerful behind a computer monitor where people don't know who they are, but that's not how we look at things.
if you were playing a game of basketball, and told someone to go kill themselves because you were frustrated about losing, you'd be penalized. Would you be punched in the face for telling someone at the bar to go kill themselves? Probably.
It's not 'PC'. It doesn't take 'testicles' to hide behind a monitor and tell someone to kill themselves or call them a racial slur. In fact, I'd say it's quite the opposite.