The guy is right. That crappy looking "4" has a curved lower half and used to be a "3"
. . . . Check out # 71. Thanks, Future Useless Eater.
The curved vertical 'stick' on the "4" should be straight, not curved, and more or less the same width from top to bottom.
Barry's "4" is very wide in the top half because it is covering up a lot of the former "3".
Plus look how wide the serif is at the bottom of Barry's "4". WOW! That is much too wide because it was taken from a "1".
The bottom serif on the 4 should be about half as wide as the letter "4".
The horizontal 'stick' mid-way up the "4" should be LONGER on the right side, than the bottom serif on the "4".
But in Barry's forgery, those are opposite. For example, look at this "4" from a 1962 use of that same stamper...
“President Obamas birth certificate was created on a Mac, in Quartz PDFContext”