So Kyokushin is pretty efficient in a street fight situation?
Not really. Real fighting is instinctive and psychological. It all comes down to if you can fight to begin with. There are common sense techniques in Kyokushin, but those would have been implemented with or without actual training in martial arts. What Kyokushin or any other legit martial art can give you is the ability to perfect a single technique to implement. A side kick or low kick is excellent as your go to weapon. It's only about realizing your own potential. Kyokushin can't give you fighting skills. Muscle fibres in your body are not trainable, and they determine the force of your strikes.
There are KK black belts that can't fight a whole lot better than average. They are slow and not explosive, don't hit that hard after training for years and don't really improve that much over time. But after 5-8 years of almost perfect attendance and dedication, you got to give that guy something so he has a black belt.
Part of it is lack of any "killer instinct", the rest I would attribute to poor hand/eye coordination and lack of red muscle fibers, lack of balance, fight IQ, etc. Despite "knowing everything", they don't counter effectively and are easy to hit. I don't see them using what they are taught, not really what you expect from a "black belt".
I was beating some of the black belts pretty bad in sparring after a year and a half or so and got my mine on year 3. After a year of training, I was sending larger heavyweights back a few steps with my jab to the body and making upper belts grimace with my left uppercut to the body while holding pads to their chest.
For me it's great and I feel plenty street safe, never carry a gun. For them, probably best to avoid fighting the more athletic members of our community. lol
But I'm "that guy" when it comes to ground grappling. Very mediocre talent at BJJ, I'm not going to the ground in a fight. Then again, I don't enjoy it, it's not fighting to me.
I don't like grappling with people, I like smashing them with strikes. Even people I like or cute girls, I smile when I see their face contort after a low kick, if someone hurts me I laugh and congratulate them. It's not about "defending myself" or avoiding pain, I always enjoyed fighting.
Gotta love what you do.