I think you misunderstood what people mean by "why" in the context of evolution.

For example, you ask a random person what his job is.

He: I fix TVs

You: Why?

He: Uh, that's what keeps a roof over me and keeps my family fed?

You: But clearly other humans do other jobs and still have roofs. So it's not a real "why". Your statement is falsified.

> Evolutionary explanations like these for "why" things are the way they are not just pure idle speculation, but they are also often unprovable, unfalsifiable, and have the same circular logic as bad religion

How DNA works at molecular level is science. How creators became what they are now is history. History usually doesn't have the same level of falsifiability as science does.