How can crippling losses be avoided?
A loss can cripple a trader if and only if volume traded is more than the amount the trader can afford to lose. Now we all keep telling each other to not invest more than we can afford to lose, but it reality nobody listens to this statement and everyone puts all in whenever the market goes down.
Again if you bought in the bull market then of course the bear market will cripple your investment - that is obviously the wrong way to invest.
In other words, there are methods to prevent a loss that can do sizeable impact on your portfolio.
-Invest only in bitcoin under the "crypto" umbrella.
-10% of your allocation for all sorts of trading to crypto, not more, maybe less.
-Say no to any altcoin out there.
-Diversify, not into altcoins, but into markets other than crypto like stocks, commodities, real estate.