Yeah, you're right crypto can easily be manipulated by people specially those have big influence in crypto, however, you have you're own decision if you want to sell everything, so next if you want to buy coins just make a research first.
But besides that disadvantage, so many people have been earning a lot in crypto. The manipulation thing is a reality and America has one of the large portions of the people using the crypto currency and this portion can act like a Whale.
Irrespective of this all, we are well off investing in crypto and making wise decisions till the market reaches boom. Invest only the money that is not needed in the near future.