It’s past the time to wonder whether athletes understand how Twitter works. It’s not that hard, especially for them, the generation in large part that created it.
In a nutshell: With few, very specific exceptions, what you post, everybody sees. Not just your identically knuckleheaded friend. Everybody.
Here’s a better question, and maybe less condescending: Do these athletes just not care? Is knowing that their small-mindedness is on display for the whole planet to observe part of the attraction? Are they’re so self-absorbed, so incapable of getting over themselves, that they enjoy it, and to hell with the consequences?
Can’t rule that out. Not anymore.