"Dark Frontier" classified THEMSELVES as "Mature Content" at one point, although I no longer see that warning on their website. That was MY source on that. Frankly, if a producer so classifies themselves, I take their word for it. That warning is now down, and at some point I plan to watch their series. If I think the warning was inappropriate, I will change their location in my website complex to reflect that opinion.
I have no idea where Randy got his opinion about the audio show. Lost Frontier. It is not classified as "adult content" at my website, and it won't be unless somebody says it should be, and justifies that, or I listen to it myself and conclude that.