Not just land and natural resources: All means of production, including infrastructure, intellectual property, capital, the entire economy.

I'm assuming no coercion. In my scenario, tier 1 doesn't need any of that except natural resources because they can self-produce everything they need from those in a cheaper way than humans can. If someone in tier 1, for instance, wants land from someone in tier 2, they'd have to offer something that the tier 2 person values more than the land they own.

After the trade, the tier 2 person would still be richer than they were before the trade. So tier 2 would become richer in absolute terms by trading with tier 1 in this manner. And it's very likely that what tier 2 wants from tier 1 is whatever they need to build their own AIs. So my argument still stands. They wouldn't be poorer than they are now.