Because you have provided evidence that can be explained just as well by smaller local processes while at the same time ignored evidence that rules out the flood.<quoted text>
How do you know that none of the 4500 year old flood evidence is from a global flood?
You still fail to understand something basic to the scientific method. Any amount of data can support a hypothesis and while that is good, it only takes ONE verified disproofof to send the whole hypothesis into the dustbin. Atacama, the ice sheets, and the absence of bottlenecks each separately and individually are enough to refute the flood. You might even explain away one of them but the other two still falsify the hypothesis. And of course these are by no means the only falsifications. Nope, wont go into them until you at leasst understand how bottlenecks work, something you have not demonstrated yet.