From an employer perspective, the next challenge is how to word a contract that allows dismissal in similar circumstances without having to pay severance. I assume the proposed legislation is designed to prevent that, at least in this context. It's going to be an interesting space to watch. Especially the extent to which an individual's social media or other personal representations are taken to be representations of the company they're employed by.
I don't think it's really going to matter. Their current contract plus code of conduct might have been fine. We don't know.
Regardless of what a contract says, it comes back to employment law.
Was the dismissal harsh, unjust or unreasonable?
Was there a valid reason for the dismissal related to the employee's capacity or conduct?
The fact that a contract might have a million clauses saying that employment can be terminated for damaging the reputation of the employer via social media posts, the employee still has the right to test that in court.