Do you call ADA as a new coin? How can? It was found in 2015 and was officially launched in 2017. I think this coin isn't a new coin. But if we compare with ETH, ADA seems too young to compete with ETH. However, in my opinion, ADA has great progress (improvement). Someday, ADA is very possible to be a strong competitor of ETH. So, don't underestimate this coin.
It doesn't need to be underestimated and also doesn't need to be compared because ETH and Cardano are not only far from age but also far from development so it's a little less feasible to compare, especially since both of them have very different prices in the market.