Commodity PCs back in the 80s and 90s didn't have error correction but they did have parity (iirc). Correction requires three extra bits per byte compared to parity only carrying one extra bit per byte. I recall around 1990 you could get your 30pin SIMs as 9-bit (parity) or 8-bit (no-parity), and virtually all of the PCs at the time wanted the 9 bit modules. Parity can't correct errors, but at least it can cause an exception when you read something that's had a bit flip.