I always thought it was more like, since light can act as a wave, it is like the wave is becoming stretched out as the space expands which creates that redshift. The light isn’t moving any faster or slower, but it has a redder (lower energy) frequency. Like a plucked string that is pulled more taut as the space in between expands. It essentially loses energy, and at some point that energy loss will be significant enough for light from other galaxies no longer being detectable for us. As well as any new light emitted from them simply not being able to overcome the distance+expansion speed.

There is just more space being added in between us and them, as if we were on a plane of stretchy fabric or on the surface of a balloon being blown up. From their (the other galaxy’s) perspective, we are doing the same exact thing, as well as every other thing that is observable to them.

*words of someone who is not an astronomer, nor a scientist.