The point being missed here is, the airline must re adjust it's cost base accross ALL departments.
Sure we could let the cc off with minimal savings, what's 10 million after all? Trouble is then you would have to let the pilots off with several million and the
terminal staff and the engineers and the transport department etc etc. A settlement would never be reached because each group would argue about how much they should pay to keep it fair.
Hence each department was set a target, each department must settle in FULL. Full stop.
Why should one department get let off just because their saving alone won't bankrupt BA?