I think voluntary mask usage indoors varied greatly depending on what part of state you were in. In my local majority have been wearing masks at supermarket, on bus and inside other shops pretty continuously since late March, whereas usage lower is south west and western Sydney and the regions.
Very few masks sighted here in Byron, i still wear one when entering shops here, and am in minority but everyone was masked on flight.
As ive not left house without a mask and hand sanitiser, the move to mandatory indoors is fine by me. I went to covid safe theatre (had to be masked) and it was fine even for that 4 hours (allowing for early seating, performance and safe exit).
I would however object if they were mandated for walking outside as they were in Vic during 2nd lockdown, as if out walking alone, keeping distance there is no upside but incredible impact of being able to breathe.