The Big Bang Theory is one of my pet peeves. I've written two medium essays on it;

https://medium.com/@johnbrodixmerrymanjr/the-confessions-of-a-cosmic-heretic-5cd4c044b8ea

https://medium.com/predict/the-webb-is-cast-72f2b8ab067d

Besides the innumerable patches required to make it world, I think the most forgotten should be the most fatal. When they realized the redshift increases proportional to distance in all directions, the premise was changed from an expansion in space, to an expansion of space, supposedly based on relativistic spacetime. Yet that ignores the essential point of SR, that the ruler and clock dilate equally, so the speed of light remains Constant. If space is expanding faster than light crosses it, then it evidently is not relativistic spacetime. Two metrics are derived from the same light, one based on the speed and one based on the spectrum. If the speed were assumed to be the numerator, it would be a "tired light" theory, but as an expanding space theory, the speed is still being used as the denominator.

No one in the field will acknowledge this, but they have no argument to refute it. They tell me to go read the books and I have. The point just gets glossed over. It's like light is some wavy line on a balloon and as the balloon expands, it gets less wavy, but this doesn't make sense as optics, as the wave behavior is a function of the motion of the energy.

I'll leave it at this, but any questions or arguments, it doesn't take much prodding to get a response from me on the topic.