Given how much of a hot mess PDFs are in general, it seems like it would behoove the government to just develop a new, actually safe format to standardize around for government releases and make it open source.
Unlike every other PDF format that has been attempted, the federal government doesn't have to worry about adoption.
XPS [0] seems to meet these criteria. It supports most of the features of PDF, is an "official" standard, has decent software support (including lots of open source programs), and uses a standard file format (XML). But the tooling is quite a bit worse than it is for PDF, and the file format is still complex enough that redaction would probably be just as hard.
DjVu [1] would be another option. It has really good open source tooling available, but it supports substantially less features than PDF, making it not really suitable as a drop-in replacement. The format is relatively simple though, so redaction should be fairly doable.
TIFF [2] is already occasionally used for government documents, but it's arguably more complex than PDF, so probably not a good choice for this.
[0]: https://en.wikipedia.org/wiki/Open_XML_Paper_Specification
[1]: https://en.wikipedia.org/wiki/DjVu
[2]: https://en.wikipedia.org/wiki/TIFF
You’re thinking about this as a nerd.
It’s not a tools problem, it’s a problem of malicious compliance and contempt for the law.
Even the previous justice departments struggled with PDFs. The way they handled it was scrubbing all possible metadata and uploading it as images.
For example, when the Mueller reports were released with redactions, they had no searchable text or meta data because they were worried about these exact kind of data leaks.
However, vast troves of unsearchable text is not a huge win for transparency.
PDFs are just a garbage format and even good administrations struggle.
I give any new document format 3 to 5 years until it ends up with similar mess. And that is if it starts well designed and limited.
JPEG?
That's not really comparable - It needs to be editable and searchable.
Photoshop and Google Images show it can be done.
Lossy
PNG