In some of these cases,, I see that it appears that the person doing the cutting is a professional,, and it shows how dangerous it can be no matter who is doing it. I used to do some tree work, MANY, MANY years ago. I have also been known to help a friend, who is a pro, from time to time,, and I also cut stuff on my place.
What most of the folks in that video do not understand it weight, nor angles, as well as distances needed for clearances. The ones on ladders are the ones I shake my head at.
Those that feel a tree service is expensive should watch this stuff & understand the dangers & what they are paying for. And even the pro's know it can happen at any time. My friend, (Tyson, for those who met him in H'burg, or Ohio,) is one of the best off the ground cutters I know. Yet,, he will tell how he knows guys who have been injured or killed who are pro's too. Had one this past summer,,, 28 yrs old as I recall,,, with many years of experience too.
Some of those clips are funny,, as nobody got hit or hurt,, but some of those,, are clearly Darwin candidates.