> it was [possible] the author probably would have just written a single paragraph in the first place and saved a whole lot of time for everyone.

This does not fit with my experience, even disregarding things like YouTube videos which drag on in order to justify longer ads.

Writing concisely is hard, and often much more time consuming than a lengthy brain dump. It's also tempting to elaborate on every point, however tangential. I have to constantly fight this in my own writing; my desire is to be complete, but really I'm drifting off-topic, diluting my point with irrelevance, making it harder to follow.

Based on the comments above, it seems like the tl;dr missed important nuance, but that isn't always so.

Obviously, a summary can't be an explanation + an argument + history. It has to be the most salient points presented alone. Think about an abstract for a paper: it should tell you enough that you can understand if you should read the paper now, and enough context so that you can remember to read it later if your situation changes.

If you feel like the tl;dr doesn't pay full respects to the article, that's fine but I feel like not many readers will mind.

edit: also thanks for writing that article, it's great.