HARM is a category of weapon which seeks things like radar or jammers. They weren’t suggesting that the jammers are literally harmless.
In unrelated news: the jammers are, in fact, harmless unless you’re making a habit of riding on top of the tank. The radio energy isn’t going to penetrate a significant thickness of conductive material, such as armour plating. Or unless you’re the person being jammed, in which case they’re a different category of harmful
The assesment that he’s the wealthiest person on earth is pretty dubious, actually. The analyses which list the worlds wealthiest people always are, because they have to decide what counts as wealth and how to count it.
Normally that’s fairly easy, but for very powerful people (who, as you point out, the people at the top of those lists are) it gets murky because of things like stocks and options which they could liquidate in theory, but which would crash in value if they tried to actually do so. Does it still count as wealth if it only exists so long as you don’t spend it?
There are also people who’s wealth isn’t held in any currency, or gold, or stocks. How do you measure the wealth or power of a sovereign king, or any other kind of dictator? You certainly can’t neatly put it in a scale alongside people who just have a dragon’s horde of cash somewhere, that wouldn’t be comparing like for like