Even if a person isn't Catholic, they still believe that the Pope has important things to say. The Pope is a world leader, and people typically respect him. Of course, not everyone will listen to what the Pope has to say, but if he can convince some people then his message is worthwhile.
This question is a bit confusing, since people can only infer that Pope Francis was aiming his comments at specific Muslim religious groups. I'm sure he meant his comments, ultimately, for everyone. In fact, the Pope has mentioned extremist groups from multiple religions, including Buddhism, called out the Korean and Russian government (on nuclear experimentation and inciting violence, respectively), and ultimately called for all countries to step up to their peacemaking efforts. He really didn't leave anybody out.
I think it's great that the Pope is discouraging killing in God's name. I think if he speaks generally and doesn't target a specific religion he could encourage others not to kill in God's name. He shouldn't stop targeting his own followers. The Pope should preach the message to all people of all religions who believe in God.
No, the Pope should not aim his message about not killing to other religions. The Pope is a leader for the Catholic Church. Catholics have chosen him as leader of their organization and they choose to follow his messages. However, other religions have not necessarily chosen to follow him. If he has a message that resonates with people outside the Catholic Church, great, but noone should be targeted with his messages.
I think that the pope should keep to his religion. Especially because if you ask just about anyone they will say that its wrong to kill for they're religion. Although the bible says to kill gays and withes and yet not many Americans (many Americans being Christian) run around killing gay people. Because if they were that would be considered too radical.