There is some of what you suggest there, more than other regions around. It is a relatively wealthy region, with a relatively high number of anti-vaxxers, still it's more that NSW, actually Australia, has been relatively covid free for months now. Except for the Victoria 2nd wave and now this Avalon cluster.
In my local area, where we haven't had a reported case for nine months, only say 10% would be wearing masks.
The long hours of waiting in testing lines, also in other Sydney areas since this Avalon cluster has come to light, is as much an indication of the prevailing attitude toward the virus as is the relative low level of mask wearing in most areas here.
It was Plato who said, “He, O men, is the wisest, who like Socrates, knows that his wisdom is in truth worth nothing”