I think that it's pretty clear that quite a few things have changed in the documentary genre, but like everything, there are good ones and bad ones.
My personal bete noire is the over-extension of stories into multiple episodes when the story just doesn't deserve it. I guess that this all follows the success on Netflix on series like Making a Murderer, and then more recently Tiger King. The former was a well told narrative, made over years, and deserving of the series length they delivered. But I believe that Netflix only came on board fairly late in the day. It was a massive success, at least by Netflix's metrics, where keeping audiences coming back for many hours is critical for maintaining subscribers. The worst case of this I came across recently was the HBO series on McMillions. It was a decent story, but could have been told in 90 minutes instead of six hours. I didn't make it to the end I got so frustrated with it.
Some of these series getting long run times are greater than series covering major wars or political figures.
The same problem is also becoming true for many fiction series where something that could be told in six episodes is stretched out to ten or more. But that's another discussion.
Then you've got the likes of Tiger King, where the story is clearly more "scripted." Which takes us into my second big bugbear - the late reveal. You see this over and over, where some major piece of information that the protagonists knew very early on, is withheld from audiences because it creates a cliffhanger at the end of an episode. I think it was the Netflix series Don't F**k with Cats that did this really egregiously, painting one person as a potential culprit before revealing a key piece of information that only 'cleared' them relatively far down the line, when in reality it happened very quickly.
If there's a clear, "We learnt this... then we learnt that a few months later," narrative arc to the story, then it's acceptable that the documentary series. But if the reveals are being scripted in after the fact, and I don't believe that's good journalism. I read that the HBO Robert Durst doc might have been culpable of that, with the makers holding on to his self-incriminating statements until much later than they actually learnt it. I understand that series, especially those with complex stories, do need some kind of structure to guide viewers through. But what we're seeing more and more, is artificially devised cliffhangers.
The corny dramatisation is also a problem. If you're producing a historical piece on Alexander the Great or someone, then of course you might want to have some CGI of him crossing the Alps with elephants or whatever. That makes sense if done well. But for grisly true-crime stories, it can just be salacious and pandering to the lowest common denominator. And if events have taken place in the lifetimes of real friends and family of victims, then this kind of thing can be simply the worst kind of tabloid journalism. Do we really need to see the serial killer attacking their victims?
It's possible to work around it. Recently, the BBC aired an excellent documentary on a notorious British killer from the late 70s known as the Yorkshire Ripper. But it was told very much from the victims' perspective - one of the problems in the case being that because many were working class and some prostitutes, they were all considered the latter and therefore, not really worthy of thorough investigation. The acts of murder themselves were not detailed unnecessarily (Don't confuse this doc with another similar one that turned up on Netflix recently. It may be good, but I've not seen it, and it'd have to go a long way to beat the BBC one. This also highlights the problem of the same stories being told over and over). And then ITV made a drama about another notorious killer - Dennis "Des" Nielsen, played in the drama by David Tennant. They managed this without showing any murders whatsoever. Again, it was more about the victims than the crimes perpetrated on them.
I think some of the problem is that the same broadcasters/streamers produce both good docs - the kind that win Oscars, BAFTAs and Emmys - and tabloid trash. The same glossy "sheen" is applied to all of them, and it's really hard to tell in advance, without knowing at least something of the makers and perhaps their previous output, whether we're going to get something good, or something trashy.
Adam