It’s true that Simpsons Did It Already, but one difference is that the PoC||GTFO files are essentially exploits of PDF readers, whereas these files are valid PDFs that comply with the spec.
If that's true, I don't even consider a Simpsons Did It. Polyglot files exploiting common tools are far less interesting ones than those that are actually within spec. Especially if the spec wasn't designed as polyglot spec.
PoC||GTFO files render correctly in all major PDF readers, so if it isn't following the letter of the spec, it's at least adhering to a common interpretation of it.
I don't think it's a bad thing at all to have another similar zine.
For example, I miss the days when it wasn't just 2600, but we also had Blacklisted 411, THUD, etc.