Where does the article say that? The US president is mentioned because there seem to be people tired of hearing about him and to be honest, US politics are really toxic - even without him.
>They could have made it unsigned instead of signed
C actually didn't have unsigned integer types in the beginning. They were added many years later and also not at the same time. For example, the Unix V7 C compiler only had "unsigned int".
That's unnecessary. But then again I can't really blame them. It isn't always clear when you have to do that. Also a previous version might have used strlen() instead of sizeof.