As a matter of fact, it's very unsafe to depend on a single coin. In otherwords, invest into more than one token by spreading your investment into potential coins but be careful not to invest into pump and dump coins. Above all, make sure to maintain risk management in which ever crypto asset you are investing in.
This is the advice that gets people to unnecessarily "diversify" their holdings into more and more likely-to-die projects — with people thinking they know what they're doing but in fact, they don't. The safest advice is to simply go bitcoin-only.