I may smurf, but I play in a fairly close elo to my main and I definitely do not shit talk people while playing. It is uncommon, but occasionally I run into pretty high rated smurfs that act like total asshats. They frequently brag about their skill, trash talk the peoples' they are playing with skill level and are often streaming.
~Plat 2 elo, enemy mid links twitch with a "duo master smurfs, unranked to diamond" title. Respectable viewer count of ~180, guy plays incredibly cocky and gets himself first blooded.
1 hard carry later...
Duo is bitching about Talon being OP and how "that Talon is just plat garbage and won't climb", then they decide to go play on bronze accounts where they continue being toxic. While it was great fun embarrassing these idiots, I do wish that people who go full asshole mode like this on decent sized streams had some repercussions.
Even in the top 20 league streams there are plenty of people who do this regularly and see no punishment. They play at massive skill differences (I'm talking master+ in silver/gold) and feel the need to degrade the people they are playing with in front of a 1000+ viewership. When these type of people become part of the top 20 streams for league I feel like it makes toxicity seem acceptable.