Long-term investment in Bitcoin is much less risky and your chances of making a profit are much higher.
Is this true? Because as far as I know, the reason people choose to invest in atlcoin instead of bitcoin is because they think it is too expensive and no longer brings big profits. So they are willing to take bigger risks by investing in altcoins with the expectation of making big profits and getting rich just like the early bitcoin investors did.
Also, I believe that everything has its price, no asset or investment is both safe and can bring great profits, bitcoin is no exception. High profit, high risk and vice versa.
Investing in bitcoin will keep us safer but I don't think it will give better returns than altcoins these days, IMO.