Disagree.
The crown is happy it is solvent.
British taxpayers are paying dearly for the crown.
You travel Europe, it is covered by caste ruins.
Many kings went bankrupt! So are many noblemen, dukes, barons etc.
There are huge expenses and little comparable income.
It is hard to maintain high life!
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.