When I was a teenager in the 1980's, the gardens were a dive, frenquented mainly by drunks. Now the location is a true hub of the city, the numbers of people who hang out there being attestation to the fact.
You mention the wall though and to me this sticks out as a piece of poor (cheap?) design. I understand the need to shield the open space fromt the bus & tram traffic on Parker Street and maybe to keep the plaza out of the eyeline
but it is very ugly. Quite why there is a need for the curved section in the SW corner is beyond me.