Anyone who can calmly shoot like that is highly trained and experienced. In NYC no less. Military, police, or professional hit man. I do not believe it was

a premeditated attack against the elite

I find it more believable that Thompson had been doing and saying stuff that other members of the elite did not like. Do not assume David v Goliath. Maybe it's war among the self-proclaimed gods. Let's see who makes money on this.