Distribution (and generation) of supers

With Avantgard, it is clear that supers exist in other nations on Earth.  The events creating super-powers are NOT limited to just the USA.

But, since we aren't reading about super-incidents in China (which houses roughly a third of the Earth's population), the indication is that most "super potentials" go through their lives without exhibiting any manner of super-powers whatsoever.

If I'm understanding the fluff correctly:

1)  Not every human being has the potential to be super.  In fact, fewer than one in a thousand have this potential.

2)  Not every potential encounters a "stress event" that activates their powers.  The majority of potential supers live normal lives.

3)  Not every potential survives the stress event, and a significant portion suffer physical or psychological damage from the process.

4)  Most superheroes are not "weaponizable", either due to lack of power level or powers unsuitable for combat.

 

Pure Theory:

Some manner of resident trauma (psychic residue energy) seems to be created with every super origin.  This energy seems to encourage/generate/be generated by violent crime.  So either superheroes and supervillains rise because of the breakdown of society, or at a certain level of chaos there are more "stress events" that generate heroes.  The issue gets thornier if the USE of super-powers generates this dissonant energy.  

 

All of the above is true, yes.

One of the implicit (but unstated) assumptions in the setting, however, is that modern environmental toxins have long-term stress effects that tend to activate the ascendant gene expression. These include EMF fields, plastics, fluoride, aluminum, etc. As a result, the populations of the world that have had longer-term exposure to these novel artificial stressors have more potential superheroes.

Over time, the rest of the world will catch up.