You'll get it occasionally. But yeah, people free on the internet to do as they want frequently unleash instincts they might normally curb if they actually had to care about the other person involved. Without actually having to be friendly/address the other player on a regular basis, and thus not needing to humanize them, it's much easier to put them down.

I try to do best 2 out of 3 when playing Smash Bros, for example, only to repeatedly encounter people who like to t-bag to troll, and immediately leave into the next game. Most perplexing are the people who stay long enough to get a single win even after losing 4 times in a row, and then go as if that last one was the only one that mattered.

Not that I don't occasionally engage in a bit of trash-talk myself, I must admit. Though I do try to stay within respectful limits. In League of Legends, one team consisted of all Tanks, who proceeded to say "You Squishies came to the wrong Neighborhood" because our team was all squishy rangers/mages. When we won, I was like "You big bois came to the wrong Neighborhood" for a laugh. In a match I had last week, I'd snuck past the enemy's frontline when they thought it was safe to approach, and got called a coward for essentially assassinating their base for the win. My response? "We take those. Got 'em." In my defense, it was absolutely hilarious and I'd do it again in a heartbeat, and I'm not even mad when an enemy successfully does the same to me.

In the words of Kratos from God of War 4: "Close your Heart to it."