I was away from crypto for years and now I'm trying to get back into the game. I was really STUNNED that there is no exchange, even after many years since bitcoin started, that we can just deposit USD and start exchanging altcoins. I hope I'm wrong because this would be the single biggest hurdle for altcoins to be widely adopted by general public. There are just too many hurdles to jump over just to START trading.
This is an issue that a few new exchanges are trying to tackle. Direct trade from fiat to alts without necessarily going through btc or eth. For beginners, they should probably first try using centralized exchanges first like poloniex or bittrex. They are easy to use