For 1080p screens at least, 170% zoom seems to be perfect fit for most content (for websites where 100% zoom is likely designed for lower resolutions) meaning sidebar ads are not even on-screen (IIRC, maybe you'd need to scroll to not see the left one but not sure how to test this).

Though I guess more sites likely don't need as much zoom to fill content, for instance Kbin is full-width at 150%. Itch doesn't have whitespace even at 100% (on the right side, the left side has it due to the left sidebar that is stuck at the top of the page).