>I'm just saying that major public formats don't just disappear, even if they become inconvenient to use; most major obsolete undocumented formats are still usable in some inconvenient way or another.

I agree with that.

> They're one possible format to transfer archived files and scans to, although being business, PDF/A is preferred over any raw image format in this group.

AFAIK, PDF/A-2+ allows J2K images, so it works there too (if you want it) and, as you obviously know, PDF/A exists precisely for digital preservation.

Also, AFAIK, Adobe hasn't allowed any other "JPEG successors" in their PDF standard, either.