I cannot say that fresh coins are always profitable. It is just because none can predict which coins are good for investment. Generally new coins are hyped when they hit exchanges. As a result, their price soars for short term. If you are smart enough to sell when their price gets soared, you can get much profits. Otherwise, you can go for established coins.
therefore at least every new coin will also be very profitable if indeed you can sell while the pump is running, because usually coins that are only hot at the beginning will pump when listed on the exchange and then just die because the developer only does it to get a quick profit without anyone next action for project development