The Lambda-CDM model is indeed incorrect, but the Big Bang theory is not. It needs some important tweaking.

Physicists are not good at creating a complete inventory when considering the beginning of matter.

They forget that they must not include that what cannot be known by physicists.

That means one cannot add the beginning of time, the beginning of space or the beginning of energy to the known beginning of matter, simply because we do not have that data. We will never have that data. We just have the data about the beginning of matter, and nothing else.

So, when physicists focus on just the data, then the Big Bang theory is actually very simple.

To make it nice and complex again, here is my article about quarks explaining our universe best. Several folks told me that it took them reading the article three times before they finally understood the structure of the Big Bang (the specific model's name is Big Whisper).

So, be forewarned. You have to bring your thinking hat for this one. Get rid of all your assumptions to understand this model.

'Quarks explain our universe best'

https://medium.com/@fred-rick/quarks-explain-our-universe-best-e03b7ccf72c3