2019 will have many of big coin as Telegram, Facebook... What will happen to the remaining altcoin?
In regardless of your question in the above, you didn't clarify or specify if you are asking about all altcoins. Because, if you are going to check the coinmarketcap especially the top 20 altcoins are most often potential coins, Ethereum, Nem, Trx, Neo, Waves, omisego and many more something like that. Which is shows that not all alts are going to die on 2019.