Rim joist insulation between 1st and 2nd floor – GreenBuildingAdvisor

An excerpt from a Fine Homebuilding article states:

Two-story homes usually have another ring of rim joists above the first-floor ceiling. If you need to insulate these rim joists, it’s best to hire a cellulose-insulation contractor.

Does anyone know why this is? What’s a good alternative to insulating a 2nd story rim joists?

Currently have the ceiling drywall tore out in a 1980s Cape Cod and trying to isolate the vented knee wall attics from the 1st floor ceiling bays and also interested in insulating the rim joists.

Is 2” of EPS against rim joists a good way to go?

Climate zone 4A in central Kentucky.

My only goal is trying to eliminate the condensation risk. There are obvious signs of condensation over the years. Isolating the vented knee walls will help drastically I imagine. Therefore, if the rim joists don’t pose a condensation risks, I’m fine leaving them as is.