That is correct, but if you go to coinbase you can use ltc, and eth for exchanging to fiat currency. There is also a exchange called coinexchange.io you can deposite lots of alts here and trade for btc, and many other new alts to be thrown into the crypto economy. But as far as bitcoin goes it will still be the safe investment compared to 95% of other coins for a long time, literally 98% of all things crypto, use btc. And will still have to use btc one way or another. Its also a means for storing your wealth. if you look at the global index, total $$$involved in a safe investment such as gold, well we are talking tens of trillions of dollars. so we are just at the starting point for mainstream adoption, we are past the early investors, now its time for the boom. bitcoin will hit at least 47k per coin when we hit 1 trillion in btc markt cap, and i see bitcoins capturing 5-20 trillion in our life time if not more. so btc will definitely hit 1 million per btc in 10-20 years from today.