It shouldn't, as it shouldn't save your preferences without you actually having pressed the button to save it, but I wouldn't put it past some web-dev to save t

It shouldn't, as it shouldn't save your preferences without you actually having pressed the button to save it, but I wouldn't put it past some web-dev to save that cookie as a default 'everything enabled' on first load, and only edit it to actually reflect the user's preferences once they've gone through the motions. Doing anything other than not dumping those cookies is a dick move in this sort of case, since the user hasn't provided clear and obvious consent.