For what it's worth, this video is an ad - I have seen it (at least the first five seconds of it) at least 20 times prior to youtube videos [1].
So I guess they wanted a YouTube add, so it needed video and once they had paid to make that said hey why not stick it on our homepage? Or something like that.
It could have also gone the other way: as a useful video describing how things works, and then it got a second life as an ad - but the former path seems more likely.
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[1] I'm not sure why they are targeting me so heavily, but I see this ad more than any other, by a large margin.