It is a very popular myth, the idea that the ego of American president is the controlling factor in the creation of the global economy. Whenever I'm talking to someone and they blame any president for "The Economy", I immediately make a tactfully silent mental note of that person's idiocy, but alas, American voters have many times over shown that this is an enormous factor if not the determining factor in their decision whether to vote and for whom...
Seriously, you probably made ten decisions this week alone that had more impact on your personal finances for the year than any president could hope to have, and most of the factors that aren't in your control - the price of petroleum, whether Amazon workers go on strike, whether the Russians take Kyiv, how many billionaires decide to sink money into Crypto this year, etc - are not under his control either.