The real world surely contains problems of both sorts.
Perhaps the real world does. But decision theory doesn’t. The conventional assumption is that a rational agent is logically omniscient. And generalizing decision theory by relaxing that assumption looks like it will be a very difficult problem.
Programs make good models. If you can program it, you have a model of it. We can actually program agents that make resource-limited decisions. Having an actual program that makes decisions is a pretty good way of modeling making resource-limited decisions.
Programs make good models. If you can program it, you have a model of it. We can actually program agents that make resource-limited decisions. Having an actual program that makes decisions is a pretty good way of modeling making resource-limited decisions.