https://www.sciencefocus.com/space/does-jupiter-really-protect-us-from-cosmic-impacts/

Granted it's not the most sophisticated article and it seems to be behind a paywall. I learned about it in a Crash Course Astronomy episode about the Jovian Moons on Youtube.

This article here found that there would have been significantly fewer impacts on Earth without a Jupiter-mass planet, but several times more if Jupiter had the mass of Saturn. It also depends on the class of bodies (asteroids, short-period comets, long-period comets): https://spaceaustralia.com/feature/jupiters-complicated-relationship-life-earth

That theory has been debunked. Jupiter hurls as many asteroid into the inner solar system as it pulls them in to crash into Jupiter or flings them out of the solar system entirely. It's a zero sum game for Earth.

What the fuck is wrong with my brain that I remember everything about that scene and can even picture it.