Manually ejecting a disc on the PS5 is similar to the PS4 and PS4 Pro. You'll need a screwdriver to turn a screw and push the disc out. Just like the base 2013 PS4, you'll have to pop off part of the ...
You can try attaching a USB mouse (the builtin ADB trackpad button won't work, if I recall correctly) and holding down the button while the powerbook starts up.
88215: Power Mac G4 (QuickSilver): How to Eject a Disc From the DVD or CD Drive discusses< various solutions, depending upon the exact situation. Especially note: If you are unable to eject a disc ...