"For decades, bench jockeys — also known as 'holler guys' — were a standard feature of professional baseball."

"The best and most effective bench jockeys, who may have owed their success to a fierce wit, a piercing voice or a penchant for creative slurs, could even cling to a roster spot after their actual baseball skills had so degraded that they were as useful to a team as an empty tin of chewing tobacco.... At the most basic level, talking trash raises the stakes of a competitive confrontation. It puts more on the line — like pride and possible humiliation — and that makes the outcome of the contest matter more than it otherwise would. It puts more pressure on the performances of all involved, both the talker and the target, and demands to know whether they can handle that added stress and expectation...."

Writes Rafi Kohan, in "Hey, Losers! Here’s How to Bring Baseball’s Very Boring Era to an End" (NYT). Kohan wrote a book about this: “Trash Talk: The Only Book About Destroying Your Rivals That Isn’t Total Garbage.”

Kohan never talks about politics in this column, only baseball, so I did a search for Trump and "trash talk," and I enjoyed finding "'He’s Like a Coach in a Locker Room Talking S__t': How Donald Trump Uses Trash Talk for Political Gain/Author Rafi Kohan on the role of smack talk in American political history—and where Trump fits in" (Washingtonian). Here, Kohan says:

Trump is in some ways like a professional wrestler. He’s cutting promos, he’s generating heat, he’s the carnival barker taking people into the arena to come see the show—and he’s getting voters who never turn out to show up. At one of his rallies, he’s also like a coach in a locker room talking s__t before a game. Can you believe what those guys are doing over there? Can you believe what they’re saying about us?...

When Trump talks down not just to his opponents but whole groups of American citizens, that plays into his hands. When Hillary Clinton talked about baskets of deplorables, that played into his hands, too. Politically, Trump’s trash talk tactics built up a very strong sense among his followers of this is who we are. And when people so strongly identify that way, when they so strongly identify with their leader, it becomes really hard to enforce any ideas of shame and more likely that you’ll reinforce shamelessness—because if you cast Trump out, it’s like casting yourself out....