Yes, threatening memes can be punishable specially if it imposes a crime upon someone or maybe something harmful to someone.
When memes are illegal or invalid?
I believe memes can be illegal or invalid if it is used for fraudulent purposes or maybe if its purpose is to commit a crime.
When Threatening is valid?
According to my research 🤓 a threat can be valid or legal if it meets the following criteria:
1st- prevent unlawful Aggression where theres physical assault or an immediate threat to life.
2nd - the threat used to defend oneself must be proportionate to the danger or Reasonable Necessity of the means employed.
Example : A, a small person, is attacked by B, a large, aggressive person wielding a baseball bat. A uses a gun to shoot B in the leg. This is likely reasonable as the means were necessary to stop the superior threat.
3rd - Lack of sufficient Provocation. The person defending themselves did not cause the fight or given the other person a reason to attack. 🫰