I'm really not sure, a lot of American cities subscribe to this district idea it's quite common to have a shopping district an entertainment district so on so forth. I'll argue for the most part it doesn't work, at least not in American cities. Unfortunately I'm not too familiar with the European cities you cite so it may be different there.
Though I agree not every area has to be mixed use, generally speaking what happens is you get just about know one actually living downtown and that makes the majority of it very sterile outside the core shopping district. Sterile / poor / and generally crime ridden. Again though this is from many American cities and there may be other factors at play.
You bring attention to some very good points here. I think that one of Toronto's biggest problems is that we're absorbed by American culture and therefore we look at fashionable American solutions to the problems of American cities, without recognizing that we've already solved a lot of those problems and really should be comparing ourselves to healthier cities, like those of Europe. Of course a few condos would be fantastic for bringing 24 hour life to an office ghetto like downtown Cleveland. Nobody would dispute that. Of course gimmicky "entertainment districts" don't work in an otherwise dead downtown and just wind up reinforcing the danger stereotypes. Light rail lines are a great way to get people to notice and consider transit in cities that have a total transit ridership smaller than that of individual Toronto bus routes. But we don't have those problems. We have a downtown that's packed with people at all hours, including (especially!) in areas that don't have a lot of residences around. We have a subway that has been at capacity for decades. We need to look at how other cities, particularly European ones, have solved
these problems.
Another poisonous idea is this bizarre principle that no neighbourhood should be a "destination" and instead people should just do all of their business in a few block radius of their home. Leaving aside the fact that this isn't the 50s and dual-income homes might require one household member to work far away from the other, every great city is completely reliant on an enormous (in some cases global) catchment area to support its businesses. In our own city, it's not like the stores of Queen West or restaurants of Ossington and Dundas are populated exclusively by the walk-up traffic from the surrounding neighbourhood. Besides, if I wanted to just stay within a few block radius, I'd have moved to a small village--it'd be a lot cheaper. But because of this strange theory, you look at a neighbourhood like Queens Quay or Bremner. We build tens of thousands of condo units and then bang our heads on our desks with confusion at why they haven't become thriving and interesting neighbourhoods. It's because even thousands of people aren't enough to support a successful urban commercial area if you don't draw from anywhere else, and because those buildings' residents are going up to Queen or College rather than hanging around their buildings.
But my main point would simply be; Why do you think these condos won't bring more retail / restaurants / pubs / lounges in their base ! Okay we replace a restaurant but what if one comes back, there are many such condos downtown that are built like this ! Retail at the base of condos works. I can see why your hesitant as there are many areas where we've seen the opposite i.e. Cityplace and the like ... but this has to do with its surroundings more then the condo base it self. There are many condos in Yorkville / North York, other parts of downtown that fit well into the streetscape and add retail. If we get this what is being lost ?
Again King east is a perfect example, all the new condos in the area have a ton of retail at the base. Okay yes, its sterile, but that has nothing to do with the buildings, it is furniture central and has always been ...
I completely agree that when you build a condo along an existing retail strip, it will tend to be better than if you build it in the middle of nowhere. But part of the problem is that a city needs more than just 15-foot deep standardized retail units. Condo boards also are extremely unwilling to rent to most independent business or to any kind of business that is thought likely to contribute noise, mess, or too many people. Their ideal is a fast food restaurant, a grocery, or a dry cleaner's that will reliably pay the rent and be an amenity for the residents rather than for the street. Furniture stores, yes, also fit the bill of a quiet, inoffensive use. We need diversity, though. A purely condo neighbourhood will mean, in most cases, identical retail units. They're not very adaptable, unlike older buildings that can change from a store to a restaurant to a nightclub back to a store at will. Another problem--and I know this is complete and utter heresy on a forum like this--is that a lot of people just simply like walking down streets with three or four storey buildings rather than lines of 50 storey buildings that block out the sun. No European city has a shopping district with skyscrapers and even in New York, many of the shopping areas are comparatively low-rise.
Also you really can't argue more people living in an area makes it more vibrant; I agree you can argue that it can lead to more pressure to have a less active night seen and that's not ideal.
I assume you meant "don't make it more vibrant" and actually, in some cases, I would argue that. You can put up tens of thousands of residential units, but if those residents just leave their buildings and get right on the streetcar (or in their cars) to some place more interesting, it doesn't really do much for vitality.
So simply put, if we make sure the base meets the street well, adds retail (and hopefully office use in the podium as well) it can work out.
You make lots of good points, and in this I hope you're right. I don't have a problem with condos and I think there are cases where the retail is done very well. I just don't think that a condo monoculture like we will see in the entertainment district will generally lead to an interesting or vibrant neighbourhood.