Yeah, the accents don't help. Not that it isn't nice to have local flavor, but tv actors should speak clearly. It's not as if fictional dialog was like natural dialog in other ways, it is made to be less aggravating to watch. Fewer pauses, fewer aborted half-sentences, and so on, so there is no reason diction should be like the reality of dialog either. Though for all I know this already could be toned down Australian dialects, but then I don't think the original would have real mutual intelligibility with Standard English.

On German tv regional dialects are often replaced by Standard pronounced with a regional accent or subtitled, because German dialects are not mutually intelligible if they are too far apart regionally. Much like dialect speakers switch to standard if they hear that you aren't a local, tv does the same. Of course due to these media and the modern mobility true dialects are getting rarer and rarer as more and more people just speak standard, because mutual intelligibility is really useful. (Hence the local one where I live mostly died out outside of preservation societies because it is so far from standard that depending on politics it's counted as separate language, and it came with economic downsides to use it. It used to be the regional written language some centuries ago, but powers shifted, and by the time of my grandparents it was mostly spoken only and its use punished in school as "wrong" etc. so most switched to standard with their children, and a generation later the dialect was more or less dead. Which maybe is bad for language diversity, but quite useful for communication.)