[gruez]

It's legal to discriminate as long as it's not a protected class.

[montagg]

There are some states, like CA, where discrimination based on political views is illegal, but it’s practically-speaking not too hard for an employer to find a more traditional performance reason that may be related to political views. Caveat: IANAL

Source: https://www.nolo.com/legal-encyclopedia/can-employers-discri...

[umanwizard]

Even then, that refers to employees specifically, and the person in question is probably not a Blizzard employees.