Karate is a martial art, not a sport.
Sports or for competing. Like basketball, football, etc. They do not have black belts.
I can't tell you about India. But in Matsubayashi Ryu (Shorin Ryu) the minimum age to obtain a black belt is 16. This is globally.
In USJA / USJF / USJI Judo globally the minimum age for black belt is 16.
The product of a mcdojo is who. Looked it up, not in depth, what I saw and read he's eight.
Kokoro is right. The minimum age is 16. 18 is best. A 1st Dan should be able to effectively defend themselves against full grown adults. An eight year old can not do that. An eight year old lacks the maturity, understanding, strength, and power, to be considered a 1st Dan.
If it is indeed this Sai Kumar kid, than that belt means nothing. Nothing at all.
In a legitimate dojo, the minimum age is 16. If they are younger then that it is most likely a mcdojo.
There is more then just physical skill in being a black belt, there is maturity as well mental factories, a child does not have the same level of understanding and maturity as an adult.
Unless you've been completely unleashed to attack your sparring partner with no regard for his potential death you're still practicing withing the constraints of rules JW, you're practicing in an organized, ruled and refereed sparring match, AKA sport.
Besides, I hardly think that's the biggest issue, eight years old is barely old enough to pick up a punching bag, let alone hit it with any kind of power. I don't think an eight year old could defend himself/herself from an average adult male.
Sai Kumar