The video is classic Bishop Williamson. It seems to have been recorded about 20 years ago.
The OP doesn't seem to be making a claim that the video is about the flat earth. The correlation that I can see between flat earth, and the info given in the video, is that both flat earther's and +W are concerned with the de-natured aspect of what has happened in society today, even though flat earthers and +W go about describing the problem from two different perspectives.
Bishop Williamson doesn't go into the scientific aspect of the problems with modern man (as flat earthers generally do) but I think that the problem of modern man today is something that +W and flat earthers have in common. Of course +W doesn't mention the shape of the earth at all, but rather he gives a good overview of the lack of common sense in mankind today. That's something that flat earthers are concerned with as well.