If this year will be a tough year for cryptocurrencies, then maybe by next year, a reversion of trend may be possible in response to this year's almost all-year-long fluctuation now. From 2019 onwards, i believe bitcoin and the rest of cryptos will also respond well.
I think next year, cryptocurrencies would be like 2017 again wherein many coins would be able to rise and then we can see some projects that matured as well because those who finished their ICOs last year or this year would have fully implemented projects and we can see now their true value and how in demand it would be in the market.
More coins would be use for its actual use case. Government would have a stricter rule when it comes to cryptocurrencies but it is better for the crypto enthusiasts because those scam projects would be lessened which would be good for the investors and it would return their trusts to the crypto projects which I would assume are slowly diminishing this year.