Chestnut
In the late 20thC the BBC made really high quality historical dramas which focused on accuracy and attention to detail. I don't think they can be surpassed. Making it 'topical' to attract younger viewers, with no attempt at accuracy, doesn't do them any favours.
Well, they were accurate as far as the evidence available at the time suggested, according to one interpretation, but I don't think they can be regarded as definitive.
I think you might be right about our brains expecting a quicker pace now, perhaps because so much information is instantaneously available now, we are not used to a slow trawl of discovery.
The Mayor of Casterbridge is fiction though, so there is a definitive version, because there is only the one book.