Funny this showing up here -- fractons are one of the first things I came across in pursuing my strange belief that fundamental particles are manifestations of defects in some "space-time crystal". But where Seiberg says “Quantum field theory is a very delicate structure, so we would like to change the rules as little as possible,” -- I have the exact opposite view: we'll probably need to tear down the vast majority of mathematical structures that are the foundation of QFT and QM, and build from scratch on a discrete combinatorial foundation. Luckily doing that is turning out to be a lot of fun and involve some interesting new mathematical ideas. But more often old mathematical ideas, like curvature, holonomy, and gauge symmetry, but resurrected in new forms.