Yes, so I have learned how to say in Cantonese "Sorry, I don't speak Cantonese, can you please say that in English?". I still get hung up on.
People complaining about expats not being able to communicate in a rather high-level of Cantonese/Chinese has started to piss me off (like whining that expats can't read a legal-jargon Chinese text and expect a translation)... Many expats DO learn some Cantonese/Chinese, it's a very long process, and sometimes we've only just arrived and haven't had much time yet to start learning and never in our lives imagined ending up here, so please give us a break!
And by the way, it's a bilingual city, whereas the UK is not... not a fair comparison.
Would you like to talk about the high level of English competency many Hong Kong locals have? Like being a taxi driver and not knowing the English word "park"?
I'm surprised by your experience. I ask the same, and the reply I usually get is "Sorry wrong lumbar." Seems they're all suffering from lower back pain.