No - since you are planning to inflict some harm to your employees, the onus is on you to prove that the harm is warranted.
Specifically, you would have to prove that sending phishing training emails with more neutral topics (e.g. a package arrived, IT policy change - ACTION REQUIRED) is less effective than sending the more potentially harmful.
In fact you should first show that fake phishing email are more effective then traditional non-phishing emails that simply warns you about the risk of phishing and gives a clear example of a phishing email without any trickery.
Something like: “SECURITY INFORMATION: Phishing emails target holiday bonuses to increase engagement. Always be on alert” along with a few points on what you are likely to see in a phishing email, how you could spot one, and what to do if you get phished.
Specifically, you would have to prove that sending phishing training emails with more neutral topics (e.g. a package arrived, IT policy change - ACTION REQUIRED) is less effective than sending the more potentially harmful.