Email spam on iPhone/iPad increases dramatically when Macbook is shut down

I sometimes travel with just my iPhone (was a Xs, now a 15 Pro) and 2018 iPad Pro, leaving my M2 Macbook Air shut down at home. When I do that, my email spam increases dramatically and my working assumption is that the email rules I set up on the Macbook to filter spam messages are disabled. I don't really understand why this happens, since I use the Apple Mail app/program in all my devices.

I assume I could just leave the Macbook running while I'm gone, but would prefer not to. Is there another way to keep the level of spam down when my Macbook is shut down for an extended period of time? Or, is there a way to apply MacOS email rules to my IOS devices?