lunarul
That type of bug is what is called “low hanging fruit”. With lots of active contributors, such bugs will get fixed pretty quickly.
Reddit migration will succeed for some communities and fail for others. Generic subs can live on with new mods and new subscribers. They’re not much different from FB or Twitter. Just mindless content to feed that infinite scroll.
Specialized subs where the community as a whole (or a majority at least) decides to move to a new home will move (or have moved already), because for those the community is what matters, not the venue.
It’s not like they planned to make it the standard test image. Just a bunch of guys working on something looking for a quick test image and grabbing the first thing they found.
Such a small section of the original image and at such low resolution would be pretty petty to shut down for copyright infringement. Especially since it was not used for profit, but for scientific research.