You can argue for the role as head of state being separate from the leader of your parliment-equivilent. And I suppose I would agree.
Whats harder to justify is the family's riches, taxpayer funding and history of behaviour that would villainse anyone else.
The Queen of England in particular is good at coming across like a sweet old nan so people adamantly opposed to the royal family have a hard time hating her. The rest of her children however I feel would provoke a far more antagonist relationships with the general public. As in to say I feel once she abdicated (or passes on) public opinion of that family will sink.
I would prefer head of states to be elected. Above all I find most people who are in a monarchy (from all countries, not jsut mine) tend to be colossal scumbags.
I think Prince Charles is seen as more divisive, but William seems very popular indeed.
At least based on this YouGov survey:
William, Prince of Wales popularity & fame | YouGov
William, Prince of Wales is the 2nd most popular royalty and the 2nd most popular public figure. Explore the latest YouGov polling, survey results and articles about William, Prince of Wales.
yougov.co.uk