That, at present, is where the wealth is coming from.
I would argue that increasingly it is not. The relative value of labor is and has been declining due to automation.
Money is their only real leverage.
It isn’t - there is also legal ownership, of natural resources and other types of property, and there is the force backing that ownership, which is also subject to automation.
If you are skeptical about the idea that wealth can exist at all independently from labor, consider the distinction between a dictatorship with an economy based on oil or mining and a more democratic country with an economy based on a diverse array of skilled professionals. Yes, in both cases laborers are involved in what the country produces, but in the latter, circumstances give them more leverage, because their active engagement and relative consent is more of a prerequisite to achieving that product. That leverage equates to a higher market value of their labor. I can imagine a future where everyone is effectively reduced first to slaves in a mine and then to skeletons next to mining robots.
Aside from friendly intent I’d say it’s close enough