You don't have a right to a "more equitable, sustainable, and diverse workplace".
I would love for someone to tell me where in any US Federal law it states you have rights to a "more equitable, sustainable, and diverse workplace".
The law states, you cannot be discriminated against based on your race, ethnicity, etc, you cannot be harassed due to your sex! You do not have a right to demand equitability, sustainability nor diversity! If you want these things, buy enough stock in the company to become a significant voting stock holder.
Activision had/has a shitty work environment. OK I get that, and if you were sexually harassed, and have a provable case, fine, make the charge. But if your only complaint is its a shitty place to work, then GO FIND SOMEWHERE ELSE TO WORK.
As far as Unions, why is it that an employer doesn't have the right to say "I will not have a union in my company!" There is no law that states every employer must have his employees represented by a union (unless Dementia Joe Biden gets his way).