Central Washington is ideal for chip fabs: tons of cheap electricity and excellent infrastructure, massive existing water supply, as/more geologically stable than Arizona, zero hurricanes/tornadoes. Three hours from Seattle is not commuting range, but it's close enough that the chip designers could easily do monthly fab visits. People underestimate how much idea exchange we've lost by separating design from fabrication.
Unfortunately Central Washington is part of a state that is known for erratic, wild, and unpredictable whims when it comes to any company whose name isn't "Boeing". It's not about taxes.