I think the more you diversify the better. If you have enough time to watch your holdings, there is no real reason not to diversify more.
Every coin you hold is another chance to make money. Obviously the more chances the better. So nothing wrong with that.
I absolutely agree with you. Also I think author is right that focused too much on big ones. For more profit its better to invest in crypto with small capitalization. Its more risky but you already have necessary baseEvery coin you hold is another chance to make money. Obviously the more chances the better. So nothing wrong with that.