Every sports journalist or athlete who has ever expressed a political opinion has probably had this insipid phrase thrown their way. It’s become quite a common refrain, particularly after the media took note that Colin Kaepernick wasn’t standing for the national anthem a couple years ago.
Like most snarky retorts it’s not meant to be particularly clever or thoughtful. It’s meant to shut down conversation and put someone in their place.
It’s also bullshit.
Not only is it ridiculous to expect a person, let alone a public figure with a large platform, to solely talk about their profession and nothing else 24/7, it’s also disingenuous because often the person saying “stick to sports” doesn’t mean they don’t want someone talking about politics.