Mutations disprove the theory of upward evolution

[Esquilax]

But all individuals of all species are accumulating the same longterm corruption. There is nothing that will make it.

Not really: there's no guarantee that any organism will mutate the same way as any other. In fact, they all do so differently, which is why we have the diversity of life that we have now; different species branch off from the same ancestral point, developing into newer, different organisms over time and many successive generations. It's why we have so many different dog breeds, for example; same species, different mutations.

And you need to stop with this idea that all mutations are harmful, or that there's some ideal genetic code that every mutation makes us stray from, because that's not true. Mutations can be beneficial, detrimental, or neutral, and though the genome changes over time, there's no inherent corruption in those changes that'll render it nonfunctional. It just keeps building on itself.

As has been pointed out to you, human DNA is mostly junk, but we work out alright.