One problem can't solve from first, if new investor can't trust new fresh coin why they don't invest in old coin. We several good coin already exists in cryptocurrency even with very low price. Even I don't think there could be a trust problem. All solution is now is the correction time!!
For me, old coins can be good for trading. And make investment is good on new project or maybe big coin for long term. That is what some people aim because new project or maybe new tokens that listed in market they will aim for short pump but big.
sometimes some new coins are full of surprises like you said. big pump but only happens in a short time. like ONE coin that doubles the price then falls. that's what short-term investors and traders are looking for.