Absolute rubbish. There's
lots of factual information here you can
know and use to make informed "guesses" (if you will).
People like Musk, who are often absolutely clueless about countries' political situations, their people, their makeup, their relationships and agreements with neighboring countries, as well as their history and geography, are obviously going to be terrible at predicting outcomes compared to someone who actually has deep knowledge of these things.
Also we seem to be using the term "geopolitics" a bit loosely in this thread. Maybe we could inform ourselves what the term we are using even means before we discount that anyone could have expertise in it[1]. I don't think people here meant to narrow it down to just that. What we really seem to concern ourselves with here is international relations theory and political sciences in general.
Now whether most politicians should also be considered experts in these areas is another matter. From my personal experience, I'd say most are not. People generally don't elect politicians for being experts - they elect politicians for representing their uninformed opinions. There seems to be only a weak overlap between being competent at the actual job and the ability to be elected into it.
[1] https://en.wikipedia.org/wiki/Geopolitics