Throwing in another relatively recent development: In-Band ECC (IBECC) (not to be confused with DDR5 On-Die ECC)
To me this seems like an interesting compromise provided that there is some better documentation made available.
Patent doc if anyone wants to get under the hood - ADDRESS RANGE BASED IN-BAND MEMORY ERROR-CORRECTING CODE PROTECTION MODULE WITH SYNDROME BUFFER - INTEL CORPORATION
Some conceptual/practical details from a vendor that is advertising this feature:
