NNW my comparison was meant to be between Canberra and Hobart for immediate access to walking opportunities - really very similar. Neither city though offers the same opportunities as Sydney to hop a regular and frequent train or bus for multiday (2 - 7 days) walks in the Blue Mountains etc.
In Canberra you only need to get out 10 km to access the start of the AAWT (6-8 weeks of walking) but I really don't want to suggest either is better - just a bit different.