If you watch/read any kind of manga related to sports, you'll know that Japan actually is the strongest nation in the world in all of sports. Although it's pretty shameless, I guess rooting for your own country is understandable, so that's not what this thread is about. It's true a lot of these stuff reads like the author has never actually seen how the said sports was ever played, but you probably have to have some kind of suspension of reality for Japan to become the world #1 in most sports, so that's also understandable.
What's particularly sad is that I notice a lot of Chinese talk about how these manga are fake because the real professional sports is stronger. Let's ignore stuff that obviously have no basis in reality. Take the legendary Slam Dunk. By setting it's basically the Dream Team as high schoolers decided to attend 3 high schools in Japan. The author literally tells you all these guys are like the young Jordan, young Barkley, and so on, and there's never any shortage of know-it-all that tells you that these guys would never make it to NBA. First of all, Slam Dunk took place in the Jordan era, so it's possible the young Ewing or slightly lesser Dream Team member wouldn't be a legend in today's NBA where the environment has evolved, but that's never the point people try to make. It's always about how the guy who is clearly meant to be the young Jordan who can dunk from the free throw line in two attempts somehow wouldn't even be an NBA worthy player. Yes, Jordan as a high school sophomore probably wouldn't be great even in his era because we know in real life it took him a few years in college before he become that good. Since Slam Dunk tries to be fairly realistic these legends do play at their high school level, and they don't put up amazing numbers because they're playing other teams that are all high school version of the Dream Team as well. But obviously all these guys are meant to follow the same character growth as their legendary counterpart.
It gets more ridiculous when you talk about things that are not even grounded in reality. For example Kuroko's basket has a guy who can make a full court 3 100% of the time if he has like a couple second to charge up his move, and he's actually pretty tall and average athletic ability for the series' superhuman standards (so probably around average in NBA). Unless blocked he will always make a 3 pointer, and I'd bet even a fairly ordinary guy with such an ability will likely find a place in NBA (every coach is going to figure out a lot of fancy setup to get this guy open, and his chargeup time is much less when in normal 3 point range). Or Eyeshield 21, which features 3 guys running the 40yard in 4.2 or less officially are clearly not NFL material, even though no one officially has run faster than a 4.2 (some claim they have done so but those are usually self-timed). Or Mr. Don, who we know can toss three cars stacked on top of each other since Gaoh can toss 1 car easily and Mr. Don is at least 3 times as strong as Gaoh, wouldn't be able to just push aside an average NFL linesman with a single finger. Heck, why not just have Mr. Don be a running back since he can obviously continue running while dragging the entire opposing team? I'm sure it takes less strength to toss 11 NFL players stacked on top of each other versus 3 cars. Speaking of Eyeshield 21, there is one guy who will never make it in the real NFL, which is Sena, the main character, because Sena weighs like 100 pounds and literally the first time he gets tackled it'd be the end of his career. I don't even watch NFL very much, but I know like actual quarterbacks slide down to avoid getting tackled, and you're talking about a guy who wants to be a running back in the NFL that is much physically weaker than even a high school quarterback. Yes he has time distortion powers and a lot of crazy stuff, but even in Eyeshield 21 it's shown that perfectly ordinary guys can tackle him if he runs straight up in the middle which is what running back do a lot of the time.
What's particularly sad is that I notice a lot of Chinese talk about how these manga are fake because the real professional sports is stronger. Let's ignore stuff that obviously have no basis in reality. Take the legendary Slam Dunk. By setting it's basically the Dream Team as high schoolers decided to attend 3 high schools in Japan. The author literally tells you all these guys are like the young Jordan, young Barkley, and so on, and there's never any shortage of know-it-all that tells you that these guys would never make it to NBA. First of all, Slam Dunk took place in the Jordan era, so it's possible the young Ewing or slightly lesser Dream Team member wouldn't be a legend in today's NBA where the environment has evolved, but that's never the point people try to make. It's always about how the guy who is clearly meant to be the young Jordan who can dunk from the free throw line in two attempts somehow wouldn't even be an NBA worthy player. Yes, Jordan as a high school sophomore probably wouldn't be great even in his era because we know in real life it took him a few years in college before he become that good. Since Slam Dunk tries to be fairly realistic these legends do play at their high school level, and they don't put up amazing numbers because they're playing other teams that are all high school version of the Dream Team as well. But obviously all these guys are meant to follow the same character growth as their legendary counterpart.
It gets more ridiculous when you talk about things that are not even grounded in reality. For example Kuroko's basket has a guy who can make a full court 3 100% of the time if he has like a couple second to charge up his move, and he's actually pretty tall and average athletic ability for the series' superhuman standards (so probably around average in NBA). Unless blocked he will always make a 3 pointer, and I'd bet even a fairly ordinary guy with such an ability will likely find a place in NBA (every coach is going to figure out a lot of fancy setup to get this guy open, and his chargeup time is much less when in normal 3 point range). Or Eyeshield 21, which features 3 guys running the 40yard in 4.2 or less officially are clearly not NFL material, even though no one officially has run faster than a 4.2 (some claim they have done so but those are usually self-timed). Or Mr. Don, who we know can toss three cars stacked on top of each other since Gaoh can toss 1 car easily and Mr. Don is at least 3 times as strong as Gaoh, wouldn't be able to just push aside an average NFL linesman with a single finger. Heck, why not just have Mr. Don be a running back since he can obviously continue running while dragging the entire opposing team? I'm sure it takes less strength to toss 11 NFL players stacked on top of each other versus 3 cars. Speaking of Eyeshield 21, there is one guy who will never make it in the real NFL, which is Sena, the main character, because Sena weighs like 100 pounds and literally the first time he gets tackled it'd be the end of his career. I don't even watch NFL very much, but I know like actual quarterbacks slide down to avoid getting tackled, and you're talking about a guy who wants to be a running back in the NFL that is much physically weaker than even a high school quarterback. Yes he has time distortion powers and a lot of crazy stuff, but even in Eyeshield 21 it's shown that perfectly ordinary guys can tackle him if he runs straight up in the middle which is what running back do a lot of the time.