That's one part of the bad mental model of organizations and markets (and thus societies) people have. The people at the top may be richer and more powerful, but they're not actually free to do whatever. They have a role to play in the system they ostensibly "control", but when they deviate too far from what the system expects them to do, they get ejected.
Never mistake the finger pointing at the Moon for the Moon itself. Also, never mistake the person barking orders for the source from which those orders originate.
That's the nature of self-reinforcing feedback loops.
Virus can kill their hosts, and a bunch of individuals can have significant harmful impact on societies.
Much like viruses, systems are subject to selection pressures over time. Systems that are too damaging to society makes society develop memetic, cultural and legal immunity against them. Systems that let individual members easily kill them are fragile and don't survive either.
Systems that thrive are ones that are mild enough to not cause too much external resistance, and are resilient enough to not allow individuals to accidentally or intentionally break them from within.
Their decisions are absolutely constrained by the system's values. They have zero agency in this, and are literally unable to imagine anything different.
There's no total ownership in structures as large as this - neither in companies nor in countries. There are other stakeholders, and then the organization has a mind of its own, and they all react to actions of whoever is nominally "running it".
The truth is, no one just acquires power on their own - people with power have it because other people let them, and they can wield this power only as long, and only in ways, as others allow it. Gaining power doesn't make one more free to exercise it - on the contrary, the more power you have, the more constrained you are by interests of those who provide you that power.