> HR and legal across the UK are probably updating their company procedures right now to include every imaginable reason they might want to fire someone.

No, they aren't because that's not how contracts or the law work in the UK. The court found that the contract enumerated a long list of breaches of contract, of which "swearing at colleagues" was not in that list. This means the court read the list as exhaustive, because it appeared to be exhaustive.

If the contract was worded differently, the court may not have used this interpretive rule. If the wording was a little more broad, the court may have worked to determine whether "swearing at your boss" could reasonably fit into the terms.