I think you're right. Obviously, she knows her son better than any other person. A lot of folks think it's one reason she's stayed on the throne so long.
I don't know how much control the Queen has over the succession, but Charles really needs to just pass the baton onto his son William and retire gracefully (if the moron can possibly manage it).
Succession is a serious problem with Monarchies over time. Even Monarchies with somewhat limited power suffer from this.
I haven’t much use for such Rulers.
There are those here on FR that defend Monarchies. Yes, it is hard to believe in this day and time. But it is so.
Privately held companies can have the same problem. I worked for 2 such companies. One is gone, the other is still strong and 150 years old. But each leadership change has it’s challenges.