Yes it is true that for long term investment you must select the best and popular coins.If you make a wrong choice to invest you will have to pay for it so simply you need to choose the best currency first.Bitcoin Ethereum and BNB are all the coins you can keep as the best coins to invest in your portfolio.The currency to invest in must see how popular the currency is in the market and what is the market cap? Especially if it is listed on the most popular exchanges?
This is a fact, because indeed if you look at the last few years currently the top coins there are bitcoin and Ethereum, then regardless of what they are, they are one that is worth keeping in the long term.
The problem is that people are panicking too much about the temporary dip right now although this is quite natural because Psychological factors would say it's very unsafe to keep coins when the market is in the red but obviously they should be more aware that selling is not the right thing to do.