It's so interesting; otherwise, there wouldn't be many replies. Permit to jump in as well.
To me, I prefer "quality" rather than "length". I'm also a reader and a searcher online, I find myself keen to read the quality content as long as it may be. However, poor articles never engages me for 3 minutes.
For readers, they are okay whether the quality content is split into 2 or 3 parts since they are interested or find it useful; they will continue reading. For publishers, they gain benefits in terms of page quantities and Search Engine Optimized keywords (the more pages they create, the more keywords they can optimize).
I agree that people now are busy and move very fast online. However, when they find something interest them, they will slow down and read. If they don't have time reading it now, they will perhaps bookmark it. I've done this so far.
My conclusion is that "length" doesn't matter, but "quality" does matter. It's just my opinion, anyway.