The impression that I get from this report is that Seattle has been gentrifying so rapidly that its minimum wage law probably has not mattered much at all. It's a place that his increasingly limited room for minimum wage work and the people who do those job.
These findings would not be especially generalizable even if this were showing an obvious and smashing success for the minimum wage increase. Which success, arguably, this does show - i.e. high-wage jobs displaced low-wage jobs, albeit mostly for totally different reasons.
What we should be interested in asking, because it's less is obvious is how would a minimum wage increase affect a place that lacks a growing economy, that lacks high-end services, or that lacks a highly educated workforce? How would it affect a place on that is on the periphery of the national economy?
(Either way, reducing both employee- and employer-side payroll taxes on low-wage employment would be a better way to put more money in the pockets of the working power without making it more expensive to employ them.)