There is far more evidence that redshift is not purely velocity based. Interstellar plasma lasma causes a redshift. We can see it in the laboratories. It depends on the amount of free electrons and some other factors.

We also know that certain "high-redshift" objects are in front of "low-redshift" objects. Usually quasars. And we see no time-delation in pulsars.

The problem is that astronomers do not want to do research into it. There is likely no expansion at all. Everything was mainly based on outdated theoretical models.

The cosmic background radiation is also falling apart, because the signal disappears outside the earth's influence. Instead we see radiation from point sources and the milkyway.

And there are far away complex galaxies that are extremely old. Note that galaxies are not collapsing. We see the oldest stars on the outside and not on the inside. New stars are formed along spirals and not via collisions. So the whole stellar evolution theory is wrong.

Have a sub /s/plasmacosmology where I list these problems.