By the definition in John's letters, an 'antichrist' is someone who starts out in the church, but then falls away from it teaching false or "anti-Christ' doctrine. So I don't know if any secular world leader qualifies under a proper theological definition. Putin does wrap himself in the Orthodox church, and likewise Trump with the evangelicals, so they have that part going for them, but neither 'came out from us' in the strong sense sense implied by John. Xi seems pretty much a secular tyrant.
OTOH, I suppose In the more Hollywood/Manichaean/pop-American-demons-are-everywhere/Satan-is-lord-of-this-world kind of theologies - any real baddy can be read as demonic and fit the bill. 👿