Let me give you an advice, a good start to become an altcoin millionaire relies upon an exchange platform. What I meant, is about, choose the best exchange that uses utility coins that is meant to be use for trading, buy those and HODL. While the exchange is gaining popularity, so as the coin's price increases, if that so, sell in the future.
Did you mean about exchanges' tokens, like Binance (BNB), and Bittrex? I don't say that what you said are wrong, instead of one of the best and easiest way to earn passive income, for investors who don't have too much knowledge, and time to follow altcoins.
However, to choose good exchanges that also have own tokens, they obviously need to have some kind of knowledge and skills in crypto.