Rewatching Rogue One, man Jyn really got sent to minimum security compared to Narkina.
Hy headcanon was just the Empire just doesn't have the resources to make enough prisons like that everywhere for the amount of people they're trying to lock up, and Cassian got unlucky.
In Andor Season 1 when Andor first gets to Na5kina 5 and they do the orientation speech it is stated that the clean sanitary conditions are not the norm for imperial prisons and that Narkina 5 is somewhat out of the ordinary.I can head canon that as just being in a transitional facility before she was moved to a much tighter and more brutal prison complex.