Boston is also pretty much unaffected. No real surprise there given that Seattle and Boston are the smallest hubs - any cut flights are going to cause a lot more disruption when there are only 1, 2, or 3 daily flights to each destination - whereas pretty much every route out of Atlanta (excluding some thinner mid-cons) is at least 4X a day with many having 10-12X daily frequencies.

LGA is also a smaller hub that had a number of cancellations but JFK can act as a reliever and typically has larger gauges.