Well, I still feel Oxford was a poor corporate citizen and should be called out for that. However, I feel there is plenty of blame to go around for the problems being discussed here.
A big one that really does not get enough coverage is the Province of Alberta and its approaches to homelessness and addictions. However, the City of Edmonton has done some really dumb things to, like the example you cited and don't get me started on why they still charge for Saturday and evening parking downtown. One wonders if they really have a death wish for downtown.
I don't think the City actually intends to drive out the remaining businesses, but many things they are doing or not doing are making the situation downtown worse. Interestingly I have noticed our our relatively new downtown city councillor who I would expect a bit more of seems to have little to say about all of this, which I think is also part of the problem. I get the feeling none of this is a priority for the city and instead of being proactive, they are just reacting politically as problems arise.