Sabo is stronger than People Scale him
*Spoiler*
All three brothers showed insane potential, and if Ace had survived, he most likely would’ve become an absolute monster after the timeskip too.
Rayleigh turned Luffy from a rookie into roughly YC2–YC3 level with only a short training period. Meanwhile, Sabo was trained by Dragon for over 10 years and even became his right-hand man.
He also showed that he can keep up with an Admiral without getting injured, and both sides were clearly holding back during the fight.
Around the same time Luffy became an Emperor, Sabo was named the Flame Emperor.
And then there’s the Imu situation in Elbaf. Imu casually defeated Zoro, who’s already YC+ level, basically while walking past him. But Sabo not only tanked Imu’s attack — he actually managed to escape despite Imu and the Five Elders being there. And we’ve already seen how broken the Gorosei are.
Honestly, point 5 alone should already say enough. Where do you scale Sabo right now? Are there actually good arguments against him being Yonko level?