Yes holding bitcoin for the long time is a good way to make money in the future
It is best time to buy and hold it a few years and you will be happy to get a lot of profit.
According to me there is fair difference between bitcoin and altcoin. Bitcoin is long term investment where as altcoin is short term investment because even today the price of bitcoin drop but there is 100% chance may be today or tomorrow the price will increase definitely. But when coming to altcoin if the price drops than the speculation will start about altcoin, it will long long time to settle in that position.