How susceptible is the NAND flash chip from physical damage

It’s my understanding that an iPhone uses NAND flash storage to store encrypted user data.

My question is: how susceptible is the NAND flash chip to physical damage that renders the data unreadable and irretrievable?

Would a hammer **** to the back of the iPhone in the middle totally destroy the data on the NAND flash chip?

I’ve been told that the NAND circuitry is very intricate and tiny so even a hair crack at this level will be like the Grand Canyon.