Lufthansa sees first class as crucial to their brand positioning, but they quite correctly don’t see a market for it on all of their flights. They’ve offered the cabin on more routes than where it made sense because they didn’t want multiple configurations of the same plane, and have wanted the flexibility to deploy an aircraft across different routes.
I wrote three years ago that I expected them to continue offering first class, just with fewer seats, and “could imagine offering just one row of first” on new Boeing 787s and Airbus A350s. The A350 is getting first class, will debut next year, and is expected to be just one row.