I think holding bitcoins could be a potential way to get rich only if the bitcoins price reaches very high level, otherwise you may earn some good profit, but I don't think this will make you rich.
There is definitely a good possibility of getting rich, but for that you need to have hundreds of coins that you will have to hold for many years. If that isn't the case, then you can make a good profit for sure, but you'll not even come close to getting rich. This is something that people shouldn't be focusing at these days. It's too late for for the majority of the people.
The method is already written, the only problem now is our inability to take that in action, that should be carefully analyze for everyone who wanted to be rich, that will not come in an easy way, we have to work for it and take time to reach our goal. If you learn how to risk then you have a chance to be rich.