I agree with the trend you mention, but the fact that it is bi-directional preference may even things out a bit.
States can focus on attracting employers by having business-friendly taxes, minimal labor laws, minimal environmental protection, and other corporate-friendly regulations. If they can attract and retain companies then people who need work will follow.
Other states focus on attracting employees by having stronger worker-protection laws, strict environmental regulations, and amenities like education/arts/healthcare/transit. If they can attract and retain people then companies who need access to that labor pool will follow.
Depending on their constraints, industries seem to gravitate towards states on one end of that continuum or the other. For example, there seems to be more manufacturing and agriculture than the US average in employer-friendly states and more technology and finance than the US average in employee-friendly states.