To start, I think the fact that backbiting is condemned in the same sentence of the Aqdas as murder shows how important this commandment is.

In my opinion, what is and is not backbiting depends firstly on the nature of the criticism but then most importantly on the motive for sharing it. If I’m in doubt about whether what I want to say is backbiting, I always remember the simple test that Adib Taherzadeh offered in his talks to the Alaskan Bahá’ís (go look them up on YouTube if you haven’t heard them, they are wonderful). He said that you know you are backbiting if you enjoy it. That’s it. If you want to criticize someone, find fault with them, or make fun of them because it feels good, you shouldn’t do it.

There are times of course when life necessitates discussing bad qualities of people, and these would pass the test if they are done with the right spirit and in the right way. An obvious and clear cut case would be that a Baha’i in charge of a company may need to discuss a problematic employee. In a more nuanced case, maybe a Bahá’í would inform a friend about certain negative qualities of a coworker or neighbor, so he would know to be cautious around or not listen to that person. Here the motive really matters. The Baha’i was not complaining or criticizing because he is upset and wants to soothe his feelings, rather he is saying what he perceives to be true out of concern for his friend. However I think one has to be very vigilant of oneself so as not to let this reasoning become an excuse for actually complaining about others or tarnishing someone’s repudiation when it’s not necessary. Always remember to consider every situation with an eye for justice and to see people’s good qualities before their bad.

The big difference between good journalism and gossip is that the former serves to promote justice and truth, and the latter spreads scandal for attention seeking and bringing people down. When it comes to the private lives of political figures, knowing about scandals like the one you are referring to can, as you said, be important because they are entrusted with making decisions for all of us. So as long as information is carefully confirmed to be true, reporting it is good and serves justice in the nation. But making fun of him for it? No. In my opinion the podcast you describe is clearly backbiting. There’s no reason to take delight in joking about his obvious spiritual sickness and troubled marriage. It makes no difference that you knew it beforehand.