Sure, it is, but that doesn't explain how it works. Previous generations made it simple, they did SECDED ECC (or sometimes chipkill) one transfer at a time no matter what the transaction size was. DDR5 EC4 can't do that, so what does it do?

And does EC8 do SECDED one transfer at a time, or does it do something more resilient?

(And sure technically it's up to the memory controller to implement, but are different controllers doing different things with DDR5?)