This is a bit of an observation about personhood in the 'My World' Setting and how it reflects how players anthromorphsize npcs
Steve i noticed seems to view the mobs more like people than they do him. Yes sure he see a bit of the mechanics and he takes no qualms in killing illigers and such and yet- he is so lonely so desperate for companionship that any deviation to the 'code' he will personify and latch onto. Heck he's attached to any kind of positive attention it seems. Even the illigers attacking him seems to be on some degree positively relieved because they're reactive. He wants to understand why they want to hurt him, he wants the villagers to be happy that they're safe. He wants the opportunity to talk down a vengeful Polly. In short he cares despite there not being much objective reason for him to- about how they feel
Meanwhile to Polly and Nil and the other mobs he's the monster, the hero, the immortal or fool he is whittled down to simple titles. Beyond ensuring he's not angry enough to go on a murderous rampage. And I think Nil is aware he's not really the sort to do so prettily. They don't really care about how he feels. They don't care to understand his intentions or motivations beyond how it immediately effects them. They know he has feelings but his well being isn't even a passing concern. He'll just come back anyway.
And it's so interesting because both the mobs and Steve are treating each other in ways that reflect player treatment of mobs and each other. The tendency to get extremely attached to random npcs and carry them around and boats and such vs the absolute disregard for even the idea of caring about them at all. Set dressing at best a tool to use in some cases. And it's neat your au is so just cool.
This ask made me very happy, I don't feel I need to add anything to your observation except gratitude, so thank you!