As for the monarchy's finances, the late Queen had a reputation for thrift and closely monitored the family books. Decade after decade of that can add up, with much of it though quickly passed on via gifts and trusts for her family. Ole' Liz and her advisers knew that large personal accumulations of cash and equities were to be avoided lest they inspire public resentment and controversy.
Charles is the same way as his mother in this respect. He’s basically cutting back on whom can receive the royal allowance to just those who are in position to assume the throne, which is basically I think, Prince William and possibly Prince Harry.