A catalog written before the lens data was read at import (RW2/RWL from v0.4.0) has none stored, and the lens correction stays off. Reload now stores the fresh probe's lens data (new journaled, undoable Op::SetEmbeddedLens; catalog format 4) and, for photos still at import settings, switches the correction on as import does. Edited photos and photos with a default-preset look keep their settings.