What exactly is the history behind this?
"Old" in this context goes right back to the original CryptoNote addresses that were merely the concatenation of the binary: version byte, public spend key, public view key and a checksum byte; then simply encoded as a plain hex string.
The single checksum byte was merely the sum of all bytes mod 255.
Since then, base58 encoding has been added, the checksum changed, integrated addresses and subaddresses.
Is there any way to generate one of these?
Easily. See above. Not sure why you'd want to though. They are longer, lack current features and likely wont work with many Monero related projects/services.