90% of bitcoin hold by whales, only 10% of bitcoin hold by people,whales can do anything pump btc to moon or dump it to hell,
BUT ask yourself 1 question: What Happens to Bitcoin After All 21 Million Are Mined? then whales completely control bitcoin price.
Bitcoin Is Not Decentralized.
1. Most probably 90% of bitcoin
is not hold by whales. That statistics are misled by the huge number of people keeping their funds at exchanges and online wallets.
2. All the Bitcoins will be mined at about year 2139-2149. Do you really care? Well, then I'll tell you something else: I've never mined Bitcoin and still have some, how come? Bought some, worked for some other and so on. Do you think that this will be different in 2149? I don't. Like any kind of money, Bitcoin will be available to buy/exchange or to work for.
3. Decentralization is something different. Decentralization is about the network. The quantity of Bitcoin hold by whales may be big, but that's because they'll use it as store of value; and in that case they'll not be so stupid to make it cheaper.
So I think that your concerns have no substance.