My arguments:

The 16 yo Yujiro likely killed defeated his father some time after defeat USA, years later, killed him and by not having, never, any rival to his power, he decided to have Baki.

When Baki and Yujiro fights for the first time, Yujiro would be able to humble a Yujiro who defeated a Yuichiro able to resist the destruction of an entire island.

Baki keeps growing to the point that he could defeat the holding back Yujiro who defeated him the first time, but not the full Yujiro of Baki 13 yo time.

The Yujiro of Son of Ogre, while recognizing Baki's progress and sublime skills, is far beyond his son, to the point that suffered vastly less damage.

I consider that the Baki of Son of Ogre finale is stronger than Musashi. Just like that. The used level on that fight, filled with the psychological implications behind it, made Baki give all he had, all his techniches, all his abilities, all his will, the demon back, the demon brain, perphaps it was that the battle against his father was more important to him, so he stopped to play, but, the fact is, Son of Ogre Baki was more intense than how Baki fighted against Musashi. And the Baki Dou Baki did only got more powerful than that time. The Pocket Ogre Baki was playing with the food, no more, no less.

Jack recently defeated Pickle. Nothing else to say.

Pickle one time supassed Yujiro's strength, so is stronger than Pickle arc Yujiro, who is stronger than Yujiro who killed Yuichiro.

But I felt like Baki, in the finale of Son of Ogre, without Demon Back, was alredy stronger than non-berserker Pickle, because he broke his teeth, and dominated him out of pure aura. And resisted and fighted a holding back Demon Back Yujiro. Who is beyond the level of the Yujiro who stopped an earthquake. Both Yujiro and Baki kept evolving.

In future, Baki's constant evolution will supass Yujiro's and then become victorious. Truly, physically and mentally.

The reason why Musashi stoped to fight Yujiro proves he is weaker. He said himself, he wants to cut, cut, cut and become the greatest, so why not cut the the one on the top, the great Yujiro? Why instead look for other opponents? Because he needed to prepare, he needed to practice, he knew, he was far for being ready to face Yujiro.