Nope. Different journalists have different talents. It's why there's a crime beat, and a sports beat, and a city beat, and a business beat... just because a story has its foot in one world doesn't mean it's not predominantly in another.
Because we're dealing with actual people here. Rumours are fine when they're within the context of the league and the business. But when you're talking about a person's life, something that affects them outside of the business, it's irresponsible to report on it without solid, credible evidence. Imagine if people in media had been openly speculating about the Karlsson's miscarriage prior to it being confirmed to be true? That kind of thing is so beyond any kind of reasonable ethical code and certainly well beyond the role of a reporter.
This chunk of your post makes me believe that you think these guys are in the business of investigative journalism, which is just not the case. They're radio personalities. They're entertainers above all else. Guys like Mendes really raise the bar because they also do a lot of digging to ensure their discussions are robust. But you'll notice any time a news story is "broken" on TSN1200, it's typically as a result of Twitter. Besides, doing "journalistic work," as you call it, on-air would be so dull and would cause listeners to change channels. If they're not getting listeners, then they're not holding jobs.