While normally the zombie nautilus is neutral, the minecraft.net article and snapshot changelogs say it becomes hostile when ridden by a hostile mob (namely drowned).
However, when encountering a zombie nautilus being ridden by a hostile mob (such as a drowned zombie nautilus jockey), the rider is hostile while the zombie nautilus remains neutral.
Environment
Windows 11 Home
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We're tracking this issue in MC-302857, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
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