Does reading a lot of Wikipedia give people a wrong idea how science works?

[Ravenshire]

If there is a shooting it's obviously not happening somewhere that really gun-free now is it?

The point is that labeling a place a gun-free zone makes it a soft target. A would-be shooter can be almost sure he won't get shot there.

Also, many of these mass shooters pick places where the likelihood of being shot is extremely low - elementary schools, churches, long-distance sniper shoooting.

That probably also plays a role, but it doesn't explain why mass shootings are less common in schools where teachers are armed compared to schools where teachers aren't armed.

(my bold)

Citation needed.

As we've seen, your opinions are rarely fact adjacent, let alone based on actual facts.

ETA: You seem to be falling prey to the myth of "good guys with guns" who will allegedly stop bad guys with guns. They are a myth.