I met Kevin a couple of weeks ago. Really nice, funny guy. Doesn't own a car, moves around entirely via public transportation. He owns two homes in Old Strathcona now.
There are so many problems, and I have been engaged on the industry and community side of this. From the industry side, the argument always is that more regulations mean higher cost which means less affordability. There has been lots of concern regarding height and setback requirements. There are some silly things that need to be remedied like how front porches and enclosed staircases count towards the buildable footprint of the house. They shouldn't and that needs to be changed.
From the community side, the standards are a bit of free for all. The zoning says here is the box you can build inside the box: go for it. Edmonton has taken the stance that there is no such thing as character. There is going to be some changes in historical areas like Glenora but not on a city-wide basis. In Ottawa for example, the rules for character come from the street you build on. No such rules in Edmonton. Wild west.
As far as displacement, it is really undeniable that infill has not resulted in more affordability. In fact, skinny homes have hurt affordability across the city. It has, however, rebuilt a lot of homes that were in tear down state. But it has come at a cost. These tall homes are often built in older neighbourhoods (for Edmonton older here means 50 - 80 years old) which are predominately bungalow massing. Infill tends to be much taller and skinnier. This constrains solar access, adds a lot more massing to the street, has not considered its ventilation outputs, has led to foundation heaves in several instances for existing neighbours, ignored neighbour's privacy as the top level balcony look down someone's backyard and provide them with no privacy. They have cut driveways into the front drive when the rest of the street is rear lane. Some of these issues will be remedied with this iteration of the mature neighbourhood overlay. Most remain outstanding. Good discussion of some infill issues by EFCL (Edmonton Federation of Community Leagues):
http://efcl.org/res/sept-2015-efcl-construction-issues-report.pdf
The issue is not as simple as stop infill though. Some of the problems stem from a few bad builders. Edmonton is lucky to have some talented infill designers. Some solutions that would work to everyone's benefit are simply not allowed do to zoning constraints and outdated zoning code. For anyone actually interested in infill, I encourage you to vote for the People's Choice Award for best Edmonton Infill Design Competition:
http://edmontoninfilldesign.ca/peopleschoice/
In July, I ran a community event to gauge some sentiment on infill in southeast Edmonton. We had 76 attendees at the event, so definitely an important issue to the community. Eventually, we presented a few priorities to city council.
The problem in my view is that Edmonton has not established a baseline community value contribution that infill needs to make. I don't think Edmonton understands what infill does and what the goal of it really is. The communication piece around it has been really terrible.
It clearly constrains affordability. Even for those who argue increase the value of my home, who cares... you are not thinking about the seniors who live on a fixed income and some who cannot afford the 30% property tax increase when infill takes off in areas like Bonnie Doon and are effectively forced out of their homes. They have lived their lives in the community and there are not always nearby options to relocate.
More to your question, builders want to make as much money as possible so will wait on the home selling. (Nothing wrong with that) There are only a handful of comparable properties. They have large margins in the realm of $100k minimum per build so they can wait for the right buyer.
