The Galaxy Store’s version 6.4.08.43 now includes the ability to disable the Device Care and Modes and Routines icons. Because these icons appear on the right side of your status bar or in the top right corner of your expanded notification shade, disabling them is more difficult than simply turning off app notifications.
With this new update, you can go to QuickStar’s main menu and disable the toggles next to Modes and/or Device care to hide the annoying icons. If you haven’t tried QuickStar yet, you should because it can do much more than just disable these two sets of icons.