I can't believe this is up for discussion. There is only one course of action to follow: obey crew member instructions and evacuate immediately on their command. If you need to travel with meds, make sure they're in your trouser pocket or otherwise immediately accessible. On a 90 second evacuation, every fraction of a second counts. It should also be mandatory for window shades to be up during take off and landing - again any time spent adjusting to darkness outside for a lit cabin is time wasted. Any passenger reaching for carry-on items is endangering lives and should be prosecuted as such.