Just because Developer Options is hidden by default doesn't mean you shouldn't unlock it. While for rooters its benefit are obvious, even for the average user it opens the door for tools which enhance your experience. From animation speed to improving gaming graphics, Developer Options has something for everyone.
Samsung Experience isn't for everyone. While it's a far cry from the TouchWiz days, it is still too heavy of a skin for Android purists. But you shouldn't let that dissuade you from a powerful device that checks nearly all other boxes — there are ways to make the Galaxy Note 9's software look and feel almost exactly like stock.