And how about if all of your coins are trash? Have you already thought that stuff?
Why they would be trash ? Are you gonna just pick one of them blindley ? you should of course do some research about them, and yes anyway even by doing so there is a possibility you lose a lot but it's cryptocurrency afterall, if you're uncomfortable risking even by this strategy, stocks would be a better option for you.
In real, purpose of split investment is if 1 of coins that we invested is bad, other will cover. It is true, people wouldn't loss in all investment because we can see in market event tokens sometime get high price too.