A few thoughts in response to that. The first being that's a pretty broad statement to make without proof. Derren Brown didn't use actors or stooges. Granted they did it that way because it's just too expensive to pay that many people and they wouldn't have kept quiet after the fact, but still - that's how they did it. Also, they can't just sit there and film over and over all day - there's a limited amount of time and money they have available to make these videos and they just go with the ones that look the best (though I will also point out that Brown included a fair amount of his misses as well).
Second thought - Stooges are an ancient and valid technique in magic, and many magicians have used them at some point in their career. But this isn't using a stooge. A stooge is someone who will make a particular selection for you, or who will tie a knot a special way, etc. It's someone who facilitates the method. What we're seeing in this video is someone coaching the entire audience to react in a specific way to something they can't even see, while exposing that method at the same time. This is not the same thing as Blaine choosing the best reaction out of 3 performances, because he's at least able to generate those reactions.
Last thought - Magic is based on deception, but this is outright lying to the people watching the video to make it seem like he's much more entertaining than he is. I think he's gotten a bit too big for his britches as they say, and can't think of how to keep up with the momentum. Now he's gone down a route that will put a stain on his career forever. Will it end his career? Doubtful. Laymen don't care and in a bit this will simmer down and no one who sees new videos will be any the wiser. Until it bubbles back up to the surface again every now and then.
Does he make it harder for the rest of us? Not really. It is the job of the artist to subvert expectations. If people expect things like what's in that video when they think of magic, I feel like that's not what you should give them. Surprise them. What was it Teller said? Make me think 2 + 2 = 5, and then astonish me with the revelation that it equals 4.
