Do you know Max Keizer? Check https://www.publish0x.com/coinbuzz/he-predicts-death-altcoins-and-hard-forks-xmmode ¿Do you think quality of altcoins projects that have emerged in recent times has improved? 
To an extent, he is right, not all altcoins will make it to the future, there are so many altcoins that will die and even if we have new ones rising, they may not get the attention that will sustain them in the market because lately, it feels like people have been a little bit more interested in bitcoin more, which is why bitcoin is gaining more dominance, and the more bitcoin gains popularity, the more it limits the chances of some coins thriving in the market.Basically, I think most of the altcoins that would see the light of the day are the ones within the top 50 in coinmarketcap aside the stable coins, because those stable coins will also varnish once bitcoin gets to a stage where it will be useful also to serve as store value, the value will tend to be a little bit stable and could serve like a stable coin.