I think even in the case of people who
appear to be productive that long (and I'd argue most people aren't productive more than 4-5 hours a day, if that) in executive positions only appear as productive as they do because of extensive support networks.
It's a lot easier to be productive long hours if you e.g. has executive assistants that manage your calendar so you don't need to think about it, people to delegate all the menial stuff to, staff at home ensuring you don't need to worry about coming home to a messy house that needs cleaning and so on.
Doesn't mean it won't still be hard, but it's not as hard as it may seem when looking up from a position you have to handle 100% on your own.
Another factor is that while e-mailing late nights when you're low down the hierarchy generally means you are working long hours, e-mailing late nights when you're high up the hierarchy can mean that, and it can also mean that you have sufficient freedom to structure your day that you've chosen to e.g. spend that day taking a long lunch and chill in the afternoon and catch up on e-mails late at night instead, possibly realising that this ironically will make it seem like you're working harder.
A lot of people who are not used to have that freedom automatically assume it's the former, and then end up falling into trying to live up to that. My advice is don't. Carve out time. Appear busy. Seeming busy ironically often makes you seem harder working even if you just say you are and use it to give you breathing room to work less.