That Knock LA article misunderstands Seattle housing, cherry-picking facts to suit its argument. The core problem is that over 80% of Seattle residential zoning is single-family, and much of the new development is concentrated where people are reluctant to live.

E.g., article cites claim that two-thirds of downtown new housing development is vacant, yet ignores the source article's immediate next sentence: "thousands of new workers... are choosing to live in other neighborhoods." Most Seattleites don't want to live downtown; they prefer to live in surrounding neighborhoods: Capitol Hill, Fremont, Ballard, the Central District, etc. But those neighborhoods are mostly single-family zoning, so existing residents are either being displaced or seeing huge property tax increases (if they're lucky). A more distributed growth plan would alleviate this.

Also re: "insatiable demand for a necessity". My demand for housing is one apartment and I'm fortunately sated. How many apartments do you need?