Have to agree with this, loved my time in Sydney.Sydney, great shore diving, great boat diving. Can dive in the harbour within view of the Sydney Opera House and Sydney Harbour Bridge and see amazing things like sea horses, anglerfish and more.
There is a but, it is so expensive to live in Sydney now, and the traffic and parking......
Still some of the best shore diving in Australia, and the deep wrecks off the coast [when I was much younger] are great [experienced divers with the right gear only] dives.