I have been strongly involved with a diminishing live music, club and arts scene since my teens and have seen it slowly fading away for many reasons. This is only 1 part of the issue but the absence of open air events, street performing (at a decent volume) and strict volume reduction/elimination for long running venues has cause many to shut their doors or revert to other means of income - pokies, high end dining and an abundance of stainless steel.
I think the noise issue has been a huge part of this in our city as it is a relatively new issue due to the growth in inner city apartment blocks for student and family living. Though this is a great thing and a must for our city it seems as though development has not been as well thought out as it should. Mandatory/subsidised sound proofing/glazing for all inner city residential living could effectively eliminate this problem.