You may think it's silly, but tech companies are actually very sensitive when it comes to social policies and how they impact their employees, given that they cater to the extremely diverse Millennial generation. Look at how they're all reacting to Trump's decision with DACA for example.
The fact is red states have a reputation of being very hostile to issues such as LGBT Rights, Immigration, etc. See North Carolina with the Bathroom Bill for instance, or Arizona with their Immigration enforcement law.
True, it may not be a major factor [[and the author didn't imply it was), but it could be a factor none the less.
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