Of course bitcoin will exist in the long term either 10 years or 15 years to the next 20 years. However, it is difficult to predict exactly what bitcoin price will be 5 to 15 years from now. We don't even know how much bitcoin will cost in the next 5 months. Bitcoin price movements can change drastically from time to time. Despite this level of price uncertainty, rest assured that bitcoin will remain in the future and more and more large companies will adopt the cryptocurrency.
What scares me about the market is that there are way too many people thinking this is just a get rich quick scheme and that's it. Many people do not think that bitcoin will be around after 50 years, there is absolutely no reason why it shouldn't be around but if people all together agree that it shouldn't and start selling then they will manage to make it go away as well. So that means, we are talking about too much power in the hands of investors who might have a misjudgment over the power of crypto.
Let's see what happens but I believe as long as we invest into btc and do not lose hope then it could be around after 50 years or 100 years and whatever, if money could sustain so much in a paper form just because governments says so, then we could also make bitcoin sustain that long easily just because we said so. There is a risk involved of course but that shouldn't really be a problem.