Yes, there will always be poor, but Gates is correct. The intense poverty will in fact be banished. The United States has been mostly oblivious to the progress others have been making since the fall of the Berlin wall, and no more so than the left, who have a Malthusian worldview that claims it is impossible. But most of the world did embrace capitalism, and is catching up.
The way things are going, in the foreseeable future, the only poor country on earth will be the USA.
New Capitalist Asia is passing us by, very quickly. 20 more years and we will be just another failed Eurosocialist state slinging resentful comments at our betters. The damage the 60’s radicals who now run our institutions have done is almost unimaginable, and likely already permanent.