I suspect we have yet to realize how pervasive questionable scientific theorizing is.

Here is one I like to point out;

If intergalactic space expands, why doesn't the speed of the light crossing it increase proportionally, in order to remain Constant?

Current cosmology presumes two metrics of space, based on the speed and spectrum of the same light.

If the speed were being used as the numerator, it would be a tired light theory, but as an expanding space theory, the speed is still the explicit denominator.

It cannot be falsified, only patched. That's why we have Inflation, Dark Matter and Dark Energy.

One way light does redshift over distance is as multi spectrum packets, as the higher frequencies dissipate faster, but that would mean we are sampling a wave front and the quantification of light is a function of its detection and measurement. A loading, or threshold theory.

Imagine how that would go down with current Quantum mechanics.

Is it any wonder physics has been spinning its wheels for the last half century.

String theory anyone?