I believe only scalabale solutions along with privacy coins will last in the long run. A majority of these coins can't handle adoption or just flat out don't have a good use case. Infrastructure like EOS has a really good chance at making even more waves. Ethereum has some scaling issues to overcome but there's still a lot of potential there. BTC's lightning network just doesn't do it for me. I'm more of a BCH fan. But scaling is still a problem for both of those too.

A lot will depend on how well these developers scale and the use case of the coin.