Major border crossings are open 24/7, others open at least during business hours. I wouldn't worry about these time restrictions. You normally travel during the day, and camp at night.
But could you list some of those time restrictions?
Restrictions like this are not new. It's just that the mapping programming is starting to include that information.
Another type of restriction comes to mind - some urban freeways have reversible express lanes (designed to ease rush hour traffic). And now they are experimenting with HOV lanes with variable tolls. But that sort of thing affects local commuters more than long distance RV travelers.