I think this is a bit shortsighted. Dylan is correct that printer stenography is, or at least was, a very obscure field. As @gottaketchumall has pointed out, there’s a lot of armchair experts proselytizing about printer dots being obvious when they hadn’t heard one inkling of it before. In my opinion, it is unrealistic to expect CGC to have developed printer stenography investigation practices prior to this issue. What we are seeing here is a truly unprecedented scam which could only be advanced by insiders. I understand how CGC screwed it up, especially when we consider that there are “legit” prototypes which were printed in 1996.
That being said, I fully agree with your point that CGC’s previously stellar error and test print authentication was an abject failure in this regard. I don’t know how CGC went from authenticating Disco Charizard and Protostoise to this. These are so far and away from traditional cards that CGC should have required much more evidence than what they were provided with before testifying to their authenticity. Indeed, many people including myself pointed this issue out before the printer dots were discovered:
I don’t think the positions of “CGC should have done way more investigation and verification on these cards” and “printer stenography was likely too obscure for them to know about” are mutually exclusive. My personal opinion is that some people took full advantage of CGC’s pursuit of publicity and profit at the expense of authentication. CGC is responsible and should be roundly criticized not only for their failure of authentication, but also what drove them to authenticate these cards. Again, we don’t know the full story and it probably involves lots of scam and fraud upon CGC as well, but as a grading company you need to expect that people are going to attempt to have you certify illegitimate items.
If I can expand on a point @pfm has made, the more obscure the item and the more easily it could be faked, the higher the burden of proof for authenticity should be. If the card can’t be XRF’d to determine accordance with a real card, if it’s literally just printer paper on cardstock, the burden of proof needs to be significant. I can’t speak to what CGC received in terms of proof, but clearly it was not enough.