Oda himself made people care about those fights
The flashback will seem random if it isn't Bonney telling the story while fighting Saturn
the only people to compare about those fights are powerscaling agendatards they still use it as such cause zoro had a bandage and sanji didnt after it was clearly stated and shown sanji can regen and has a faster recovery timeframe now...
people wanted to see how zoro faired against a child mihawk with insane powerups.... weather it be a zorotard wanting to wank him to all hell even more than ZKK and sanjitards ready to shit on zoro if he struggled...
oda didnt make people care for the fights they were really nothing in the story theyre children with df abiltiies their own cloned genes and lunarian bloodlines giving them superior base stats all around. theyre strong enough as children they replaced their actual counterparts who are in their primes and adults...