When the forum thread becomes more critical of the channel than the YouTube comment section.
Seriously though, he did disprove some of the methods that seem to make sense on paper, like lowering the resolution.
And about his baseline, yes, none of us would do any of those things because we fully understand the limitations of our device, but not the average Joe, the targeted audience for this video.
When someone like my mom buys a laptop, she would think that the advertised battery life of a laptop is what she would get out of the box, regardless of her habits and use case, and this includes things like leaving the keyboard back-light on even during daylight. Of course, sooner or later she's going to find out that the battery barely lasts for a few hours, nowhere near what she was promised. So, she quickly runs to google and starts looking at how to get more mileage out of her new device; and as Linus showed in the beginning of the video, there are some very weird (and potentially dangerous) ways being recommended, so much so that even to some of us computer geeks, it makes complete sense (i.e. lowering the screen resolution). So this video in some sense helped to objectively show which of those "tips and tricks" actually worked and if so, by how much.
I guess what I'm trying to say is that this video (like a build guide) was not meant for most of us, who already knew how to get the most out of our devices, and where our expectations should lie regardless of what the manufacturer claims.
Regarding the "clickbaity" title, I think Linus already explained this somewhat in the last Honest Answers video, it works and that's just the way YouTube is. Personally, I don't think this video was as clickbaity as it was trying to poke fun at other clickbaity sites and videos.