The analogy that is most appropriate is the inchworm crawling on an expanding balloon, as the speed of light, relative to the expansion of the space.

The problem is that both are metrics of space. Remember we use lightyears as the universal measure of cosmic distance.

As Einstein said, "Space is what you measure with a ruler."

So which is space? What is measured by the light speed, or what is calibrated in terms of the redshift?

If the "real" space is what is expanding, what is light speed measuring, if not space?

When cosmic redshift was originally discovered, it was assumed to be classic doppler effect, but than when it became apparent that it increases proportional to distance in all directions, it meant that either we are at the center of the universe, or cosmic redshift is some sort of optical effect.

Some years ago, I came across the following paper;

2008CChristov_WaveMotion_45_154_EvolutionWavePackets.pdf

It makes the point that while single spectrum light will only redshift due to recession, multi spectrum "packets" will redshift over distance, because the higher frequencies dissipate faster.

The problem this causes for the larger field of physics, is it would mean we are sampling a wave front and not getting individual photons traveling billions of lightyears, which means the quantification of light is a function of absorption and measurement. Basically a "loading theory of light."

Here is an interesting FQXI contest entry, arguing for just that;

https://fqxi.org/community/forum/topic/1344

As for Dark Energy, if this effect compounds on itself, that would far more effectively explain the curve in the rate, than assuming most of the universe is otherwise invisible energy.

Dark Matter is another topic, but I suspect we will come to see mass as an consequence of the centripetal effect of gravity, rather than gravity as a property of mass.

Waves tend to both synchronize, which is centripetal and harmonize which is centrifugal. Thus space being measured as both curving in and curving out, equally, in an overall balanced relationship. Omega=1.

So the excess centripetal effect, currently associated with Dark Matter, is synchronization across a much broader spectrum of energy.

Thank you for being thoughtful. Having been following this topic for some decades, I've developed a fairly thick skin, for those who are unwilling to imagine beyond accepted theory.