Personally, I have yet to comprehend how a high level wizard could take out a small army, much less a large one.
There far too much hyperbole involved in this claim, IMHO. And perhaps not a bit of class warfare (as shown by that last comment)
People shouldn't focus on what others have and get jealous, it's not very productive.
When people lack a resource that they think they need, and they see some other guy has it, it's not just jealousy, it's a need for that resource based on the imbalance.
It's not just a rich people vs. poor people thing. Warlords in Africa hold power over their subjects. That guy in Cuba seems to be doing alright for himself. Stalin had a pretty good run.
People in power tend to stay in power. People subjugated under them seem to have difficulty changing it or having the will to risk everything to attempt changing it.
some people come to tyranical power with no problem or opposition (and are even promoted to such positions). Others make a grab for that power and are swatted down.
Results are mixed on whether any one wizard will be able to make a grab for power and keep it. For a variety of reasons.