Nah, Yamato's Durability hype is considerably better:
She could withstand a barrage of cannon fire:
This was implied to be something abnormal by Momonosuke:
It's not just that Yamato tanked a barrage of cannon fire, it's that her doing so was implied to be something abnormal. "How are you fine...?!". This wasn't just normal resilience, but there is something exceptional about her body that let her remain unscathed.
It's plausible that Yamato inherited Base Kaido's abnormal durability. Either that or her Devil Fruit is a Mythical Zoan with exceptional durability that Yamato retains even in Base.
I'll give this to Jack because he could fight for 5 days non stop.
Unknown. Yamato's Devil Fruit is likely much better, and if Jack's endurance is because he's an Ancient Zoan, Yamato's Devil Fruit may make improve her Base much more.
Alternatively, Yamato's durability should be much higher, so she's more resilient regardless of whether Jack can soak more damage than her. It's that much harder to damage her than to damage him.
Jack is also more experienced.
- Yamato stalemated Ace in Base.
- Yamato was superior to G2/G3 Luffy in CQC.
- Yamato has fought against and been trained by Kaido.
Honestly, I don't think Base Yamato has any business being weaker than Jack.
@Kromage911.
Honestly, once Base Yamato shows Haoshoku cladding, the question wouldn't be "is Base Yamato stronger than Jack?", but "is Base Yamato stronger than King?".