This seems to be a non-issue. The linked article says, "A BA spokesman said: 'We will always do everything we can to accommodate smaller musical instruments in the cabin.

'In order to ensure there is enough space for all customers to store their belongings, larger instruments, such as guitars and cellos, can be carried in the hold."

The article is an excuse to show a CEO looking furtive and two women in various tight dresses. One shows a trumpeter with her dress about to fall off. That's what it's really about.