I don't know your definition of work, but to me, to have every minute of the day from waking to sleep scheduled for at least a year ahead, and most activity during that time be determined by a committee (even when you have some say, which often you do not), would be hell, and is most definitely not leisure. It involves little or no power, and little ability to use the wealth, that comes with the throne, for whatever you might like to do with it. And if the word leisure means not-work, what the monarch does is work by exclusion, even if it isn't breaking a sweat. What is scheduled varies from meeting and conversing with complete strangers (even if they're arrogant boors or pompous idiots) to visiting places you never knew existed (never mind whether you do or don't want to go), eating whatever is put in front of you (when you know the chef has spent inordinate time and effort on it), having your health status reported on continually etc. Which raises the point that everything happens in public, with no privacy at all. I wouldn't want their job if it was the last job on earth. (I don't speak for the rest of the family, though it's hard for them to get a normal job because of who they are, not what they can do; that was Harry's major problem - he just wanted to be a soldier; Philip and Charles did a fine job of creating something out of nothing; don't we call that entrepreneurship? Andrew is an ass, Edward at least married well. And there's an other point: the whole world has opinions on everything about you, even if they really know nothing about you!)
The case for the defence rests here m'lord.
Tax to follow.