* Not Risky
Maybe a better term is "less risky". Although we do know how volatile cryptocurrencies are compared to stocks, forex, gold, and real estate, at least responsible long-term investments negate the effects of constant ups and downs in the market. But I will never call long-term cryptocurrency investing not risky. If it is not risky at all then there is no need to create tips like watching its volatility and investing only a portion we can afford to lose. If there is no risk, then we can just all-in invest all our funds allocated for long-term goals.
Yes, that should be the correct term, every investment has risk involved, and so much with crypto because of it's volatility as compare to stocks and other assets. The thing with crypto though is that it's cyclical, meaning that every 4 years we might see a good returns on our investments.
And long term? it could be defined as 1 year or 4 year or 10 year hold, so it's really up to the individuals on how he/she will look at what long term investment mean.
For the criteria for altcoins, it's going to be difficult as we can see even one of the biggest FTC collapses.