Well, of the top highest marketcap coins btc, eth, usdt, bnb, usdc, xrp, busd, ada, doge, and matic, I can say I am a holder of 7 of them. The only ones I do not have are usdc, busd, and matic.
The tendency of people to choose gems
in an investment is very limited to the few that are available, because representatives of some others cannot survive under certain conditions, even if they are in the top 10 of coinmarketcap. I prefer bitcoin as a long-term storage asset, as it has proven to be able to retain investment value, whereas Ethereum and BNB are only used under certain conditions to make a profit.
So yes I think it is a good tactic to have as many top 10 of them as you can. I think most people will invest in those coins with highest marketcap since other people have invested more then 710 billion dollars in them already!
Everyone has their own pattern in choosing coins with large market capitalization, the goal is to get the maximum return when investment power is at the planned stage, the selection of certain coins can also vary and according to individual beliefs and tastes, but already it's becoming a habit for people to take references based on coinmarketcap's top 10 and I think that's a good tactic to use, as long as we've done a small analysis of the coins we want to invest in.
Bitcoin is one of the best coins ever, so investing 70% in bitcoin is the best way to maximize it, while the other 30% can be chosen according to individual tastes with various considerations of previous analysis.