Here's the thing. The accomplishments of the underlings are typically always overshadowed in comparison to that of the accomplishments of the Captain. This is why the news reports are riddled with headlines like "Luffy and Law take down Doflamingo", or "Luffy invades Big Mom's territory and leave it in shambles." Therefore the perception of those characters to the rest of the World are never going to be as great. Kaido, Big Mom, Shanks, Blackbeard, Whitebeard etc.. will always have that spotlight in the newspaper.
Oda himself is the one who hyped Katakuri to this degree, through the eyes of first hand accounts from his crewmates/siblings. We are not given any reason to believe otherwise. He never once showcased any of Big Mom's children to be bias. Brulee had no qualms diverging information that Snack was defeated by Urouge, and no qualms about reporting that their "Invincible Big Brother" was defeated by Luffy. This is something that would have never reached the outside World, had Brulee never opened her mouth. Even someone like Bege who was playing the Big Mom pirates from the offset was the very first person to hype Katakuri. Revealing that he has one of the rarest abilities in the World. This was further hyped through statements made by Rayleigh, by reaffirming how rare it is.
We know for a fact that the Yonkos have been clashing with each other for years. So to assume that Katakuri has never fought anyone noteworthy is pretty shallow, as we would have to assume that everytime Katakuri went with Big Mom to fight with one of the Yonko's, they didn't bring their own commanders for some odd reason. From a narrative standpoint, that makes no sense. "Yeah, he's undefeated, but that's because he only fought scrubs." If that was the author's intent for the readers to reach that conclusion, then he would have done a much better job in highlighting that fact. His siblings would not have such a hard time believing that someone like Luffy took down Katakuri if in reality they knew their brother really only ever fought and defeated low level characters. To them it was inconceivable that Katakuri lost. That stems from a genuine and honest belief through first hand accounts that their brother is just that strong.
Oda himself is the one who hyped Katakuri to this degree, through the eyes of first hand accounts from his crewmates/siblings. We are not given any reason to believe otherwise. He never once showcased any of Big Mom's children to be bias. Brulee had no qualms diverging information that Snack was defeated by Urouge, and no qualms about reporting that their "Invincible Big Brother" was defeated by Luffy. This is something that would have never reached the outside World, had Brulee never opened her mouth. Even someone like Bege who was playing the Big Mom pirates from the offset was the very first person to hype Katakuri. Revealing that he has one of the rarest abilities in the World. This was further hyped through statements made by Rayleigh, by reaffirming how rare it is.
We know for a fact that the Yonkos have been clashing with each other for years. So to assume that Katakuri has never fought anyone noteworthy is pretty shallow, as we would have to assume that everytime Katakuri went with Big Mom to fight with one of the Yonko's, they didn't bring their own commanders for some odd reason. From a narrative standpoint, that makes no sense. "Yeah, he's undefeated, but that's because he only fought scrubs." If that was the author's intent for the readers to reach that conclusion, then he would have done a much better job in highlighting that fact. His siblings would not have such a hard time believing that someone like Luffy took down Katakuri if in reality they knew their brother really only ever fought and defeated low level characters. To them it was inconceivable that Katakuri lost. That stems from a genuine and honest belief through first hand accounts that their brother is just that strong.
If not for bb and luffys progress god knows how long it would be since they seen each other.