shining the light on mental illness is just another form of "othering".
you only have to look at the desperate clamour to label anders breivik as "nuts".
I'm no quite sure what you mean by "othering".
"there's "them" and there's "us".
"we are not like them."
"we wouldn't do the things they do."
"they are dangerous."
the "mentally ill" are not any more statistically violent than any other group within society.
hardly any mental health diagnoses carry with them an increased propensity for violence (towards others*) above the norm.
indeed given many of them are on drugs that regulate how they emotionally respond to the world, are under some form of observational scrutiny, and tend to avoid everyday drugs many of us take for granted because they don't mix well with their condition and/or medication i wouldn't be surprised if they were, as a group, actually measurably less violent than the rest of the general population.
the crime figures certainly seem to reflect that.
in addition there is a huge percentage of modern Americans who are now "officially" mentally ill (60% or more i remember correctly) due to the fact they have been diagnosed with a mental health problem and/or take prescribed mental health medication for a mental health condition.
this line of application, much the same as taking aim at "gamers", is about ascribing "otherness" to seemingly distant subgroups in society to remove the very idea that they may be like us.
"i would never get angry and shoot someone."
"i'm not like that."
truth is most people are.
the vast majority of all murders are still due to a "lapse of reason" in an otherwise "normal" life committed by someone we know for interpersonal reasons.
and people really don't want to think about that.
i mean REALLY don't want to think about that.
in fact you would almost assuredly be "mentally ill" if you went through life thinking, either consciously or subconsciously, your family, friends, acquaintances and work colleagues were the most likely people to kill you.
that's not a normal state of being even if it does, statistically, reflect truth.
hence "othering" (in this subject and many others)
everyone has times in their life they wanna lash out.
one of the problems with guns is that they facilitate that possibly meaning death via "the push of a button" and from that point there's absolutely no way to claw your way back.
we are not perfectly rational beings (even when "sane") and "violent thoughts" are part of what we are whether we like it or not.
ultimately our aspirational rhetoric does not actually tally with where we are as a species.
we aim high, but we fall short and jails are full of people who made "big mistakes".
if you like have a read here on the real of "dangerousness" of mentally ill people :
* i'm excluding "self harm" here.