It's great how Hong Kong tax is always quoted as being so low yet rent is the true tax.
Crew can be spending around 25-50% of their total renumeration on rent to live to a quality of life they expect to provide to their family to match the life back home and this is why people are leaving.
BA might pay a total package that's less on paper but lifestyle wise it's now better off long term.
Sadly seniority traps many before they can make the jump