What I'm trying to say is that, the future of cryptocurrency can't be predicted at all. We know that past performances is no guarantee of future results. What happened in the past might not happen in the future. I'm optimistic when it comes to Bitcoin, and the whole cryptocurrency, but I can't just remove the fact that there might be a chance that we might see a new invention in the future that would be better than crypto. I mean I don't know what it is, but anything can happen, right?
I guess what I will say to you OP is that, if you believe that crypto will still be there for the next 5 years, invest into it, then sell after 5 years or at least during that time frame. You asked a wrong forum when it comes to that IMO, and nobody can answer you that accurately that's for sure. I guess just Good Luck OP.

It's hardly a dark future, but I see the future of cryptocurrencies and in that future, cryptocurrencies are not the same as they are now. There will be more regulation and more KYC in the future, no matter how much privacy advocates would like it. And cryptocurrencies will be seen as a product, a utilitarian product, not another pump and dump. Anonymous teams and developers will disappear from the industry and the market will live by the same rules as the stock market does now. There will be almost nothing left of the original concept of anonymity and privacy. This is how I see the future of cryptocurrencies.