But that's exactly what they were hyped for. When they get their ass beat they get up very shortly.
Anyways let's wait for raws or further information
Who got up fast? Ulti?
While everyone else from F6 and Calamities never woke up again. Once they down, they down. The hyped one is their durability.
Sanji didn't have enough AP to KO Queen. Franky had to look for Sasaki's softest part (stomach).
Wait a sec. They might be hard to be taken down alright. Like Jack in Zou and Queen by Sanji's words. But it has more to do with endurance and not recovery. We never see any injured ancient zoan suddenly can heal their wounds.
Biggest strength of ancient zoans: durability and endurance. The recovery is BS bro.
While in this case for King and Queen. Although they probably have great endurance (big Max HP), their endurance (max HP) is already depleted by Zoro and Sanji. So now, without treatment, their HP is not much better than when Zoro and Sanji defeated them.
Ancient zoans have big max HP (endurance) and defense (durability). But not recovery (regen), it is special for Marco.