It's put forth in an amusing fashion,but is true historical fact. They have papers on the net if you can find the sites with more info. Like from Pat McGovern,a micro biological archeologist. He also worked with Sam over at DFH on his ancient ales series. The rest would be in writings & such.
It's amazing when you see things like this. Beer pre-dates baked/leavened bread by nearly 3,000 years.
They study these things for a living,so it tends to follow that they know more than we on the subject. This video just doesn't get bogged down in all the mind numbing details. Besides the fact that they do show some proof here & there. I just can't read cuneiform.