To be fair, English may be an 'official' language here but I would say that many can't speak it and most don't speak it well.
That said, you can get by perfectly well without it...on the other hand, blind people can get about perfectly well with a cane!
I think you miss out on a hell of a lot if you can't speak Chinese, but that isn't important to everyone...
So here we have an argument between folks who place a high value on knowing the local lingo and the benefits that flow from that and on the other side, people who don't find it necessary...
Let's avoid the usual dogpiling shall we?