Today, the lives on digitally:
To understand the longevity of the Karaoke CDG, you must understand the "Subcode." On every CD, there are bits of data that control the track numbers and timing. The CD+G format hijacks the unused to store low-resolution raster graphics (typically 288 x 192 pixels).
One of the biggest nightmares for a DJ or KJ is an internet outage. If you rely entirely on a cloud-based streaming service, a bad Wi-Fi signal can ruin a gig. A physical library of karaoke CDG discs does not require an internet connection. It is reliable, tangible, and immune to licensing disputes that might suddenly remove a song from a digital library.
During this time, the term became synonymous with "karaoke disc" even though other formats (like DVD karaoke) existed.