I have been doing some looking, and I find no evidence in history that cosmological redshift was ever examined as matter of basic physics of light by hardcore physicists.
And yet, that is the very first thing that needed to happen.
Also, redshift seems to be the norm of the universe. There are some examples of blueshift, but these seem to be pathological.
The prevalence of redshift and its interpretation as Doppler shift (and later, stretching of space) have resulted in the view of the exapanding universe. From that point on, the Big Bang Cosmologists have been gaming the system for nearly a century.
The Big Bang Cosmologists today sit in supreme confidence on a beautiful flying magic carpet of the Doppler expansion and under a showy umbrella of its verification by space age technology.
That umbrella I have taken away from them. Now perhaps it is time to pull the rug.
What if this redshift is explained within the foundation of physics, in the very nature of light?
What is special about light in the cosmological setting that we have not had reason to consider before?
It is this: A light field at the limit of infinite dilution (infinitely small energy density).
What happens to light then and why?
Something to think about for those with physics in the gut.
I have suggested some considerations here.