alt Hacker NewsProcess-intensive, but higher compression has clear strategic value. Distant satellites such as Voyager, where bandwidth is severely limited, could transmit more data using such capabilities. Equally, for long-term archival storage, improved compression would allow far greater volumes of data to be preserved on durable, life-long media formats.
Distant space probes are power constrained though.
It's entirely possible the degradation of their RTG power sources would be more expensive doing the compression then just sending the data as is.