Gotta love those overly-sensational-clickbait-titles. Thank you for saving me from the pit of lies I've been putting myself in all this time.
You have to realize that many of your favorite YouTubers did not build a fan base because of long 30 min Let's Play videos. You are just seeing the aftermath of their success. They most likely started with action packed very well edited content that had only the funniest moments after hours of footage.
("You have to realize." Lol. But if I start nitpicking about the language you choose, and how you are in no place to be a figure of authority, I could go forever, so I'll pass on that)
30 minute Let's Play videos? Way to exaggerate. Tell me one "favorite YouTuber" that has 30 minute long Let's Play videos that might have confused our tiny little brains into thinking it was the correct way, master (oh, of course not the occasional 1,5 hour long video PewDiePie and alike put out every once in forever).
You have absolutely zero ground to stand on your statement. Since 30-minute-Let's-Plays are not a thing, let's talk about real and popular Let's Play template which is around 15-mins. And surprise surprise, Syndicate, Jacksepticeye, Markiplier, Pewdiepie and many other "favorite YouTuber"s have 10+ min Let's Play, starting no later than their first 10 videos.
That still doesn't mean, "Hey look they succeeded, so let's make 15 min Let's Play videos!" of course, since when they were doing those videos there were not a billion other people doing more or less the same thing.
To conclude, logicwise I would agree with your thoughts but when I looked at my channel stats I surprisingly saw that my long, relatively unedited Let's Plays had way better audience retention than my other videos. This new information made me think again and now I'm experimenting before coming to a conclusion if I should go with longer let's plays or heavily edited shorter ones.
You, on the other hand are bold enough to use imperative language based on a generalization, your hunch and zero credibility.
After this post I don't want to see any negative comments about the purpose of this thread.
Sir, yes sir.
Seriously, Get your attitude in place.