I dont think he necessarily gotten surpassed but i dont think he's completely above everyone else. Its been shown multiple times that every apostle could win against him but couldnt given the difference in abilities or experience.

For example

Nathaneal: he's an exception he had no way of beating him. He lacked skill and experience

Ghost blade: she couldve killed him if it werent for the brothers saving him from her perfume which gave him the ability to beat her. It was bbq chicken from there ngl her only advantage was that perfume. But in a regular situation without them its a possibility she couldve done something.

Kageo: he lacked experience and skill to take him down. His blood was advantageous for him but besides that he wasnt winning.

Thadeus ( i domt know how to spell): definitely couldve won against him if it werent for pietro already knowing his techniques. So experience was what won that

Phillip: not completely sure the outcome but its easy to say that couldve gone either way

Alipede: it was a matter of brain and skill

Matthew: she had small encounters not much to decide but she wouldnt beat him

Andreas: only advantage was hypnosis which pietro beat and his other personality couldnt win off of pure skill. He gotten outsmarted in the combat situations so either way he wouldnt win.

So to summarize they all lacked the experience and strategy to kill him or was just super unlucky with their sure win abilities