legitimate

"This nature of this talk, and the jokes made about the guests, are often judgemental however, and many failed to see these talk shows as legitimate discourse. Here is Michelle who uses the strategies of distancing, as well as delighting in the pleasures of story, to negotiate her relationship with them." (Matt Briggs "Television, audiences and everyday life")

I'm not sure how to get it, legitimate meaning 'justifiable' or perhaps 'authentic'?

Personally, I think "legitimate" here means: worthy of any consideration/discussion; having any merit/worth...

It could also mean discourse that follows the accepted rules. Being judgemental and making jokes would be against usual rules of debate. One of the definitions of the word legitimate is "conforming to the law or rules," and it comes from the same Latin root as legal.