No, Bitcoin is not coming to an end; no, it's not a Ponzi scheme.
Bitcoin will recover. Will it go back up to $20,000 a coin? I don't know, but who cares. Maybe it will go over $100,000 a coin. However, remember what Bitcoin is. It is a peer-to-peer cash system that is not controlled by government or banks. It's a system where I can send money to anybody, anywhere in the world. Success will be the day when I can use Bitcoin to pay for all my daily goods and services with it.
Does Bitcoin have problems? Yes. However, these problems will be fixed over time. Maybe Bitcoin Cash, Litecoin, or Dash will become the cryptocurrency of choice, but one of these projects will become a normal part of our daily lives. At the same time, protocol projects like Ethereum, NEO, EOS, or Cardano will become the main platforms for new and upcoming decentralized apps that will change the way we live.
It is unclear how this will all unfold. The crash of 2018 is in progress. It might keep going, it might reverse, it might stagnate. I don't know. Read some technical analysis reports (but remember, they just report probability, not facts).
I do know what I'm going to do during these hard times: I'm going to wait. Lots of news about Ponzi schemes, corruption, hacks, and government regulations have covered the headlines all over the Internet. It's unclear what the market cap will be tomorrow; it can be a bit scary.
However, once the dust settles, it will be clearer to me where I want to continue to put my money. It will make me more confident in the future of blockchain technology.