How to Turn Off the Screen Magnifier in MacOS Ventura
Most other answers miss the point, which crowds out the answer most users are looking for. Most users don't care about the settings, they just want to turn off the magnifier and get back to what they were doing. That's why the question is more like "Turn Off MacOS Screen Magnifier" than "Disable MacOS Screen Magnifier".
To turn off the MacOS screen magnifier in Ventura, press and hold Control, then swipe down on the trackpad with two fingers.
MacBook Pro 16″, macOS 13.6