I think one of the reasons why Bitcoin trading is the best and the best is that when one trades only Bitcoin, his profit will be less than other coins or tokens and vice versa the chances of losing from other coins or tokens will be much less. I personally think that Bitcoin can be the only product for long-term trade management or long-term planning.
Do you think there could be anything other than Bitcoin in terms of long-term planning?
In trading you can use the token you feel like using and especially the one you know that will not be bother to you, but when you come in terms of long term investment, i will encourage you to make use of Bitcoin for investment and skip some coins that doesn't have good potential, because those coin's that doesn't have potential do die off on the way of long term investment and especially during when cryptocurrency is having long term bearish, while people advice people to use Bitcoin for long iterm investment, it's because of it's potentiality.
That's why Bitcoin is also the king of crypto because it has no doubt about its potential,
maybe only a few coins are really worth a long term investment,
besides Bitcoin I think Ethereum is another option for that.