being volatile is not the problem and it can not be considered a "risk" in my opinion. take a look at bitcoin ,it has been volatile for all its life but it still is a very good currency and/or investment. the reason is because volatility is the product of having a small market on exchanges.
the problem is when volatility is not because of smallness of the market but it is because of manipulation. for example no matter how much money goes into altcoins they will remain highly risky because their volatility is product of pure manipulation which people call pump and dump.
The smaller the market for a coin the higher the probability of manipulation. That's why investing in Bitcoin is less risky than in any of them. But I agree that even for BTC the market is still too small for it to be stable. How big the market should be is a big question, but I think it should be at least 10 times bigger than it is now. And that's perfectly possible, by the way, because BTC is used by less than 1% of the world population still.