Please keep as is.
I realise concentration spans are decreasing but all that will happen is that everything will be shortened to 10-second sound bites like we get on the News.
People that cannot concentrate for 90 minutes or however long need to pause the video and come back later.
There certainly is a lot of information presented with much of it very confronting in terms of challenging our long held beliefs. These are much like University Lectures of stuff we need to know but is difficult to hear. Some other video's, where it's a three hour lecture, it literally takes me a week to watch, but they are the best video's ever.
So I do agree that watching some of them in one sitting can be challenging.
"Losing Detail" is not the answer as far as I'm concerned. I'd suggest that viewers break them into smaller pieces. I think over time, once this becomes a 'collection', the problem will then become indexing and finding a particular word, phrase or concept that you remembered being said and then finding it in an index.
So I'm really in favour of preserving the Detail and Quality of the works.