The part about "give up stock options for nothing" sounds awfully close to a threat to retaliate against workers for unionizing. In that context, it comes across rather close to the stereotypical mob indirect threat: "Nice house you have there; shame if something were to happen to it."

My personal feelings are that if a company needs to resort to threats and retaliation to prevent unionization, then the workers do deserve to unionize, because the company clearly is willing to trample on any worker who dares threaten its authority, and only collective action on the workers' part is likely to counter that.