I used to think diversification help reduce risk, my reasons was that It would help in a case where Bitcoin drops in price cause my other coins would still be intact not until I tried it and noticed that when Bitcoin dips, most other Alts dips with it so I had to perish that mindset of diversification and stick to holding Bitcoin, it is the best coin when it comes to investment and doesn't have much risk factor cause even when the price dips you could still DCA and recover losses overtime. infact, so far an investor is thinking long-term which is the main principle of investing in Bitcoin, the dip or fear of price drop shouldn't be an issue so far the investors keeps DCAing at various Intervals over time. Therefore, instead of diversifying I think an investor should channel such energy and funds into accumulating more Bitcoin, I've got to understand that most investors don't understand the DCA method and how helpful it is towards Bitcoin Volatility and that's why they'll be diversifying their portfolio with shitcoins instead of using the DCA to accumulate more bitcoin periodically.
Diversification is Good, could be considered one of the best strategy of investing, your approach was what was wrong.
Never place all your egg on one Basket no matter how much you trust a project.
Investing in Bitcoin and Shitcoin is not diversifying, it's more of placing some egg in a basket and another where giants could fight this destroying the egg
This would reduce the benefit of the Good basket.
Personally, I prefer diversifying but only invest in Bitcoin as a Cryptocurrency and dabble in some stock and lil land (though you can't do DCA in this).
Investing in Bitcoin and shitcoin is like farming tomatoes and rearing chicken in same place.