Bad/Junk emails don’t take much time. You just unsubscribe from them or delete them. Maybe a quick-but-nice “no” if it’s warrented.
Good emails don’t take much time either. You’re excited. You want to write them or reply to them because they mean something good. They don’t feel like a time sink, they feel like accomplishment.
It’s all the emails in the middle that are the slog. Emails that need attention, but they aren’t exciting. They require work, but work that really doesn’t amount to much. There is some satisfaction to getting through them all, but it’s unfortunate that that bulk of work is ultimately going to be worth so little.
It’s worth strategizing how to slim those medium emails. Either demote more of them to bad and shooing them away, or promoting them (shaping them) to a more exciting place.