Yes, it could be the fastest way to get rich but it could also be the fastest way to get broke as the market is very volatile. One just have to be smart enough in trading/investing in cryptocurrencies.
That's it.
Fastest way to make money, but also quickest way to lose all of your money too. What goes up, eventually comes down.
As for becoming rich, it depends on how much one defines as 'rich' and starting amount. If someone has 1K to invest, it may take a bit of time to become rich.