Okay, sure. If you mean townhouses or something, lower density by urban standards, mid density when you consider the countryside exists too. I really, really don't see how the sustainability of anything benefits from that. You need more roads, more cars, more land and more building materials to house the same number.
If you just mean building the same kind of apartments somewhere else, like in Kamloops or something, you haven't actually changed anything except more roads and traffic again, because everyone is further from everyone else.