They certainly don't need to be seeking improvements that benefit every single employee. For example, employees seeking to get paid maternity leave would be a p

They certainly don't need to be seeking improvements that benefit every single employee. For example, employees seeking to get paid maternity leave would be a protected activity even though it doesn't benefit all employees. The KKK or porn examples would be an exception because it would create a hostile work environment for some employees to even suggest that, not because it would only benefit certain employees. If Damore had only been trying to organize action to get improved work conditions for conservative employees, that would be protected activity and the NRLB opinion says as much. Google was careful to make clear that they were only disciplining him for parts of his memo that were likely to create a hostile work environment for other employees, that is something that they are not only allowed, but possibly required, to discipline employees for.