In crypto it doesn't make much difference diversifying the portfolio among different currencies, because all of them are affected by bitcoin's fluctations after all. If btc pumps, altcoins also pump and if bitcoin dumps, altcoins simply dump as well. A diversified crypto portfolio would be interesting if altcoins had independent life. The only advantage of holding different cryptocurrencies is that one of them might present superior percentage appreciation, so you are highly benefited if you hold a decent number of those tokens. But that is a kind of lottery anyway.
It does since not all cryptos are the same. If you diversify on the wrong coin, you will lose big but if you will only stick on one to two top coins, you won't possibly lose but you will only earn as long as you know how to HODL when the market is in bear. BTC can influence other coins but I think not all times and also not all coins are affected with it. This is one of the advantage of diversifying, because when BTC is dumping some of our assets can still rise or vice versa.
We can increase our chance of hunting a potential token if we will do a research and not just by picking up randomly according to our instincts. If you do that then you will say that you are like playing the lottery.