Peter,
Dark energy came to be because gravity was supposed to slow the rate of expansion, but it doesn't.
Einstein originally proposed the cosmological constant to balance the effect of gravity "contracting" space.
According to our best measurements, the visible universe is flat, ie, gravity and expansion do balance out.
These three points are not mine, but accepted conditions.
So now gravity does exist and does contract our measure of space, yet the light from those distant galaxies is redshifted such that they appear to be moving away, relative to distance. One point to keep in mind though, is that we can only observe light which hasn't been absorbed by these intervening gravity fields and what is lensed around them would have been light much more spread out, but is only focused by passing close to them. So the only thing which appears to expand is the most undisturbed light. Virtually everything else in the universe, from the densest to the lightest mass and all light drawn into these gravity wells, falls inward. Then remember the only source of this light is what is being radiated away from these gravitational vortices in the first place.
Now the assumption that light can only be redshifted by recession is based on the presumption that quanta of light do travel as point particles, yet it would seem evident from that two slit experiment that they actually travel as waves and are only absorbed at points by atomic structure. So it would seem quite likely that light expands when released from mass and contracts when absorbed by it. In fact, it seems mass is essentially contracted light/energy.
Now wouldn't the quanta of light having expanded be a very good reason for light to be redshifted?
As I keep pointing out, the expanding universe theory still assumes a constant speed of light, ie. lightyears, against which to judge this expansion and as Einstein said, "Space is what you measure with a ruler." So if the ruler, ie the units space is denominated in, remain constant, against this expansion, where is the basic mathematical logic in saying space expands, rather then they are moving away in space????
It seems to me what really exists is a cosmic convection cycle of expanding radiation and contracting mass. Which then either burns off, or is ejected out the poles, radiating for billions of lightyears. Then we don't need those enormous patches of inflation and dark energy, or, I think, dark matter, since gravity would be an effect of mass condensing out of energy, rather than just a property of mass, but that is a longer story.
The cosmic background radiation would simply be the solution to Olber's paradox, the light of ever distant sources, redshifted off the visible spectrum.
Instead the attention is now on whether you would burn up, or be stretched out, falling into a black hole. Fighting over the details, while the big picture makes no sense.
Regards
John M