You are right Bitcoin stays strong even when politics and economies get shaky. And we know that Bitcoin is not tied to any country so fights like US China trade war do not directly hurt it. In fact when inflation rises and economies struggle Bitcoin limited supply could make it even more valuable. It has survived past crises and proven itself as way to protect wealth. While governments play their games Bitcoin just keeps doing its own thing its price depends on how many people use and believe in it not on political drama. We know when traditional systems fail Bitcoin role as safe backup only gets stronger.
As you said, the price of bitcoin depends on how many people use and people's belief in it (supply-demand). But did you know that political dramas have a direct impact on the global economy and people's finances? When the economy is in trouble, people's income will also decrease and from there they will limit spending, investment...so bitcoin will also be affected. That is why whenever the world economy is shaken by geopolitics, war, epidemics...bitcoin is often dumped in the short term.
In the long run, geopolitical uncertainties will not affect bitcoin as it will adapt, but in the short term, we cannot deny that bitcoin will be affected.
Not just bitcoin, every financial investment works like that.