“Catholics and Muslims do not worship the same God. However, they worship the same God as Protestants.”
What does John 3:16 have to do with what you posted? I mentioned the creeds because they addressed heresies regarding Christ and the Godhead.
The creeds define what Christians believe, including John 3:16.
The bottom line is Jesus is coming soon. There are worldviews who want to eliminate Christians and Jews, and we as Christians (Catholic & Protestants) need to stick together to be light to the world.
Right now the world sees us a separate entities, different faiths, but we worship one God, one Savior, one Holy Spirit.