As someone who doesn't know anything about karate i was always sceptical of hearing about so many kids with black belts in my local area growing up. I had a kid in my year who was a black belt in some form of karate, and he even had pictures so he was obviously telling the truth, but one day he came to our mma club after school just to watch us muay thai folks spar. As the class was ending, one of the club member's friends from the year above came in just to walk home with his friend, by crazy coincidence he was also a black belt in some form of karate. Upon learning that both of them were karate black belts and had never met they decided to spar. Now, i'm not a karate expert but the black belt in my year couldn't lay a finger on the black belt from the year above and it had nothing to do with any physical advantages. That day i learned not all black belts are created equal.
I honestly wonder sometimes if that guy went on to achieve anything at world level or if he simply gave up after highschool.
Here's an article on the kid from the year above me back in the day -
https://www.examinerlive.co.uk/sport/other-sport/karate-huddersfield-fighters-golden-return-5011184
"Then came the men’s turn and saw Lewis O’Gara slaughter the opposition to take gold in men’s over 5’10” light continuous and gold in men’s over 5’10” points."