Why does observing a finite amount of light from a finite distance contradict anything about the range of electromagnetic radiation?

Because the range of electromagnetic radiation is infinite. (And light is electromagnetic radiation, FYI)

So that's what we expected to see. Infinite light.

But that's not what we saw.

Light does not come from 1 trillion light years away. It does not come from 20 billion light years away.

It makes it to Hubble's Limit, c/H.

This wasn't expected.

To explain its redshifting into nothing, one answer is that space is expanding, and if space is expanding uniformly (which we now know isn't true by a long shot), then it would have began expanding 13.8 billion years ago.

Therefore, in theory, only 13.8 billion years existed for light to travel. And that's why you don't seem to think there's a problem. Because you can solve it with some new logic:

Here's the recapp:

In theory, light travels to infinity In observation, light comes from finite distances
So in theory space must expand (v_galaxy = HD)
So in theory only a finite amount of time exists in physics
So in theory, no problem, we see finite light because of finite time

Of course, the evidence against the 13.8 billion number is so overwhelming, they invented an inflation period to magically fast forward through a trillion or more years of it.

Even then, all the examples in my OP describe how the theory still doesn't work.

If the sun goes around the Milky Way once every 225 million years, then our galaxy has formed in less than 60 spins. Starting to wonder why cosmologists have no legitimate theory of galaxy formation? Now consider trying to explain galaxy that look likes ours that formed in 20 spins. That's what the new observations ask of us. Completely out of the question. Except, now we have dark matter, which can basically do anything arbitrarily, just like dark energy.

Here's the alternative:

Observation 1. light doesn't travel to infinity
New Theory A. light doesn't travel to infinity (v_photon = c - HD)

Crazy, I know.

Some people say "hey, that challenges relativity!", well, it challenges the applicable limits of Maxwell's equations, upon which relativity is based.

Some people thought Newtonian Mechanics is how reality actually worked. We are now smarter, and we know Newtonian Mechanics is an approximation of reality with a limited domain of applicablility.

For some reason, though, the idea that relativity is an approximation that has its own limited domain of applicability, is scary to people.

It's all part of this idea, that you can believe science, because science questions itself. Yet once its called science, people are reluctant to question it.

(edited for formating)