> So why have the videos attracted millions of viewers?
People seek meaningful and purposeful activities and have mostly given up on them for themselves. In the realm of protecting the environment, they think things like "If I do X by the rest of the world doesn't, it won't make a difference," so they give up. They give up similarly with values, hopes, and dreams around work, family, fitness, politics, and so on.
They don't realize they've abandoned their values. Watching others live by theirs reminds them that you can live by your values. They dream they might follow as they passively watch, their muscles atrophying and waistlines growing.
Maybe some will get off their couches, stop looking for "out there" by airplane, and instead looking inside to realize they could do what the guy in the videos does. Or at least try.