There is nothing wrong with the block. Even this simple GPU only block has very similar fins and spacing to a Byksi or EK one. Should perform the same within margins of errors. VRAM and Mosfets are pretty well cooled with the original Heatsink and fan sh
The 2080ti Hybrid includes an aio cooler which is made by the market leader Asetek.
Its not poor quality control, its chemistry.
There is a potential of 2 electron volt between copper and aluminium. If both materials are electrically connected, electromigration starts to eat away the aluminium. The radiator will leak soon.
That is why you cannot put normal water in the loop. Manufacturers use non conductive liquid and special inhibitors so that almost no electromigration takes place. As soon as you open it, the liquid can get contaminated which will make it conductive again. Inhibitors also don’t last forever, so every all in one has a built in self destruct.
The only solution is to switch to a copper radiator. the block and pump are usually fine. But the microfin array is where the corroded aluminium will build up. You likely replaced the wrong part.
looks like it. you can still use it in a nas. just connect it to a usb port instead of sata, it should be fine except possibly limited SMART Info.