What is being removed to make way for this planned building? It would be a shame to lose any of those old homes and apartment buildings in order to satisfy the perceived requirement for higher density living in Portland.

And, as a life-ling resident of this city, can some please explain to me why, exactly, high density living is the answer? I would prefer to buy a home with a yard and some space between me and my neighbor, rather than to be stacked one atop the other the way things are headed. This is Oregon, we have space, why can't we use it?

"Low density living" contributes to urban sprawl by spreading development up to and beyond the growth boundaries. It increases dependency on cars to get to homes in the outer areas of town, increases public transportation times and traffic. Ultimately, the people with the money tend to live in the more expensive places, which are more convenient, and lower income earners are pushed to the outskirts. This perpetuates the racial and social divisions in towns and neighborhoods.
(Or those with the means live in the pretty suburbs, drive for hours daily, use up resources, and contribute to waste.)
Eventually, the outskirt communities, neglected by planning committees, attract opportunistic businesses like payday loan companies, fast-food joints, strip clubs, etc, but don't attract sidewalks, bike lanes, or thriving local businesses. This spreading of development also kills off what was there before: small farms and forested lands, healthy habitat for many besides humans. Examples of this: the stretches between I205 and Gresham along Powell Blvd, along McLaughlin Blvd, etc.

On the other hand, high-density living is planful, less wasteful and more socially healthy. It doesn't mean tearing down victorians with nice yards for concrete buildings. It means purposeful communities that promote walking, biking, public transport and don't necessitate driving to a strip mall to get basic foods or supplies. It means local businesses rather than chains, less fast food, more healthy choices. Less traffic, less time commuting, affordable housing for people with less money not segregated and walled-off from fancy expensive condo dwellers, but rather incorporated, with financial incentives.

If we want Oregon to look like Anytown, USA and strip malls to spread from border to border, we should continue to old development practices. If we want Portland to be its own unique place, we should look to keeping development close to urban centers, and avoid spreading beyond growth boundaries.