As far as I can tell no domain expert thinks that is an actual issue. You are at this point wondering if a magnetic activity event MIGHT occur in the future tha

As far as I can tell no domain expert thinks that is an actual issue. You are at this point wondering if a magnetic activity event MIGHT occur in the future that then MIGHT have some indirect effect on clouds that then might impact global warming substantively. We might also get a supervolcano eruption which would cool things for a while!