"Below a certain distance (0.5m-no diskussion about that!) - dangerous due to the hot gases"
Please read ony of my writings above (someone copied here). The thing is dangerous within some centimeters.
And in REAL selfdefence situation it is the last thing I worry about, the health of the attacker.
"Above a certain distance (1.5-2m) - no effect on the attacker."
I think it is underestimated.
Maybe true for rimfire patrons.
Last sylvester I fired a couple of 9 mm PAK CS-patrons (for fun:-)) from my GRPK-9, and the effect of 3 fast, following shots was a more than 3 meters long, half meters wide, almost untransparent white CS-cloud.
"And I appreciate the pepper spray in their equipment, as a non-lethal solution."
The pepper-spray's only advantage, that it is cheap as the dirt. (and easy to carry)
There is no psychological effect (schreckwirkung) so, you MUST use it. The gun shaped gasguns are often enough to show.
It is easier to aim with handgun shaped devices (not a bad argument in case of dog attack), and you KNOW how many shots you still have. In case of a pepperspray you don't know how many left in tha flask.