Karate is trained to improve one's skill in karate in the same way that BJJ is trained to improve one's skill in BJJ. That there is crossover for self defense is incidental. People don't train karate or any other specific style of martial arts with a self defense emphasis. I believe that to be crap. People train to improve in that style, and most hope or believe their style overlaps with self defense to some degree.
Actually, I've yet to have a single student join my program for the purpose of learning NGA. They join to learn some physical self-defense. So far, none have even known what NGA is before starting. So, yeah, people do study specific arts for the purpose of SD. I've never started any art for any other purpose. I've met people who started arts for many reasons, and easily half of them start martial arts primarily to learn physical self-defense. And that includes folks who got into wrestling, BJJ (I know an instructor in South Carolina who added Gracie JJ to his programs simply to beef up the groundwork for self-defense training), karate, Judo, Aikido, etc.
Now, do folks STAY in MA to get better in the art? Sure. While I still have a self-defense focus in my training, at this point my largest motivator is simply to get better at what I do. So my personal training is more focused on getting better at NGA at this point, but that doesn't change that for many years (and upon starting every art I ever studied) my primary focus was on self-defense.
I'm not sure how you draw the conclusion that "people" don't train in any style specifically to develop self-defense skills. That's like saying people don't join a Zumba class to get fit - they do it so they can learn Zumba.
yeah. Okay. If you accept this, I really don't want to hear any more BS about anything else. If a thrust kick is self defense, then I really don't want to hear anything about how BJJ isn't realistic. If you're saying in ga thug thrust kicking is realistic self defense training, please for the love of Pete never suggest that ground fighting is unrealistic.
I've never said ground fighting is unrealistic. I think it's a bad idea to get into it in a SD situation, but a good idea to know it so you can deal with it if you have to. Nothing "unrealistic" about it - it's just not the place you really want to be (on the ground) in self-defense.
As for "BS", I think your unsubstantiated claims about others' reasons for studying MA would fall in that category.