>If a power loss causes the flash to scribble on the wrong SSD location (e.g. the tables that keep track of good and bad blocks), the SSD "dies".
The problem isn't that data is corrupted in the flash, the problem is that the devices' own firmware (the SSD's embedded controller, which is a tiny computer in itself, "boots" from that) is stored in the same memory used for data storage. They could've gotten around this by not storing the firmware on the actual NAND used for data, but a separate device (or kept it inside the controller itself), so any power loss may cause data corruption, but not render the SSD completely unresponsible and inoperable.
The problem isn't that data is corrupted in the flash, the problem is that the devices' own firmware (the SSD's embedded controller, which is a tiny computer in itself, "boots" from that) is stored in the same memory used for data storage. They could've gotten around this by not storing the firmware on the actual NAND used for data, but a separate device (or kept it inside the controller itself), so any power loss may cause data corruption, but not render the SSD completely unresponsible and inoperable.