Pretty much this. A short video is a fairly strong indication that the author did his work and respects your time, while a long one is a fair indication of the opposite. I've come to recognize some red flags in longer videos, such as including unnecessary bloopers, reading very slowly, reading long and frequent definitions, going on tangents, and generally not synthesizing the information enough such that all the bits presented tie into the main topic.
I would lie if I said that I don't consume long form documentaries on Youtube. I do and there are some channels that I deeply enjoy. But for a while, especially since they removed the dislike button, I've become wary of discovering new channels. It's often hit or miss, and the overall time investment doesn't look justifiable in retrospect. For this exact reason, I've removed all my subscriptions, and disabled all recommendations. I mostly poll for channels that I remember had good content that was meaningful to me.
I would lie if I said that I don't consume long form documentaries on Youtube. I do and there are some channels that I deeply enjoy. But for a while, especially since they removed the dislike button, I've become wary of discovering new channels. It's often hit or miss, and the overall time investment doesn't look justifiable in retrospect. For this exact reason, I've removed all my subscriptions, and disabled all recommendations. I mostly poll for channels that I remember had good content that was meaningful to me.