> I suppose that this isn't surprising because wherever there is a mystery, they can ask for money from politicians. Taxpayers like you and I pay for it.
Or a confederacy of dunces. Same difference.
The dunsmen of Scotist thought were once famous for their brilliantly labyrinthine, obfuscating logic until the enlightenment started and people began making fun of their pointy hats. This is just how ideas evolve. I think tired-light would bring more clarity and unity to physics as a discipline.
Physicists already acknowledge that the quantum vacuum is not just geometrical space. They'll even write it about it roiling and bubbling. My guess is that it won't be too many years before they realize that there is a spacetime superfluid that is very lightly interacting. Then it is just a logical step to determine what kind of particles are in that superfluid. Maybe tired photons and tired neutrinos eventually lose enough energy that they begin a phase change into another state that doesn't zip around at high speeds. Maybe those low energy particles combine into some other low energy particle (a graviton?). Perhaps the spacetime superfluid temperature is 2.7K black body and is what we erroneously detect as the CMB from a big bang that didn't happen. If you follow this thought process, the idea that photons could very occasionally lose some energy harmonics to particles in the superfluid is entirely sensible. This would cause a very slow redshift. The observable universe would be limited by the distance a high energy photon could travel before losing so much energy it joined the superfluid. The fields of physics and cosmology need creativity and to start thinking on new ideas, like this or others, because it is very clear that they are on the incorrect track at the moment.