Say I open an Electrum wallet, I get BTC addresses belonging to it and they are supposed to be totally unique. But say at the same time another person at the other end of the globe opens an Exodus wallet, who is to say he will not have 1 or more exact same addresses in his new wallet as me?

I know there are a trillion different combinations possible with so many characters in an address, but how do all these wallets make sure no duplicate addresses ever get generated?