You cannot change the default behaviour for this type of menu item as it is toggled on and off depending on certain events...for instance turning it off and then dragging out a guide line will automatically turn it back on.
Anything you do to automatically turn 'Extras' off will more than likely be overuled by some other event almost instantly....so pretty much pointless [globally] turning it off really.
If you must have 'Extras' turned off by default then it can be done via a script but its a lot of effort for something which may just be toggled back on again soon after.
I can go through setting up the script although to be honest its rather like flogging a dead horse.
I would follow IamSams advice and selectively choose what is shown rather than turning everything off globally.....also Use SHOW EXTRAS OPTIONS as seen at the bottom of the 'Show' menu in IamSam's image above.