The problem isn't the YouTube videos. It's that you are trying to prove something doesn't exist. Of course that's not going to work.
The connection to an MA discussion isn't "prove to me that all {insert style here} training is bad." Rather, it's "show me that SOME {insert style here} training is good." You can show me videos of bad BJJ or BJJ not working in various contexts. But I can also show many videos of very good, high level BJJ working in a variety of contexts, from street fights to MMA matches to BJJ matches to "style vs style" challenge matches. While we can be sure that some BJJ is not good, we can also determine without doubt that some is VERY good.
YouTube is great for substantiating the affirmative.
If you continually asserted that electric cars are slow, and I told you an all electric Datsun 1200 could run 10.4 seconds in the 1/4 Mile topping out at 117+MPH. Hard to believe. If I show you a video, we now have evidence.
If I said that it routinely beat the crap out of a lot of other cars, including corvettes:
[MEDIA]
Masaratis:
And even other electric cars, like this Tesla (quietest drag race EVER)
I could show you dozens of videos, and can invite you to find your own. I have provided, I think, AMPLE evidence that an electric car can be VERY fast. This video footage will support all of the other evidence, such as discussions about consistent torque, which also support a position.
The only thing that can't be recorded in this day and age are vampires. Are you saying that vampires are involved somehow?