I think if you are asking about controlling price I would like to say about demand and supply policy. Actually no one sepecifically controll the price of bitcoin/ if the demand increase but supply low amount could be raise the price. Also holders are responsible for controlling price. If you hold it will raise if you sell the price would be low . It's simple

It is simply the law of supply and demand, OP.
The volatility is could be because Bitcoin is global, well almost due to bans imposed by some country.
Media, influencers, etc indirectly affects the price that pushes investors to either dump or buy.

The price of the bitcoin depends on the supply and demand, if you know that term in the economics that is also similar with bitcoin if there would be a lot of people who keeps on buying then the value of the product will increase the same as with bitcoin if there would a lot of people who keeps on buying then the value of bitcoin will increase as well vise versa in the selling of bitcoin.

The following are all influence regarding the bitcoin price. But bitcoin whales has the major influence regarding the price of bitcoin. Recently many customers experienced a higher pumping of bitcoin price, that is making some people to asked what is the causing of bitcoin pump?. Supply and demand are the caused of bitcoin pump in the exchange market. When the suppliers are few and demand are much in the market, the price of bitcoin will increase to cause many investors to achieve  much from their Investment.

Honestly, none of the people you have mentioned in the thread has "full control of the price".

1. Bitcoin whales? Yeah, they do have some "influence" in the price, but that's a short term influence. Any actions taken by them affect the market shortly (and recovers back quite quickly).

2. Nope. Banks have nothing to do with the price of bitcoin. At least for now.

3. Wall streets are going to be the last guys over here.

4. Same as wall street.

5. Top crypto exchanges can have some influence in the market if they manipulate the prices. But I doubt any honest exchange does anything like that. Even if they do, it's going to have a long term affect on the market, which people will eventually realize and move away from centralized exchanges.

6. Crypto Influencers can' control the price, but can manipulate it for a short term.

Of course those buyers and sellers of bitcoin when they gonna sell nor dump their bitcoins then you knew what is going on because thats the time that the bitcoin price will going to decrease but an good opportunity for those who wants to buy or invest into crypto and mostly those big exchange sites that has a good people who has a lot of coins that can be a thing. But it will always be in people and the supply and demand of bitcoin. Ofcourse you can see em in the graph when there are movements into it.

In my opinion, this year bitcoin price control is by Institutional investors and bitcoin whales. The major influence on bitcoin has institutional investors regarding the bitcoin price. If we see this year's bitcoin movement so far we notice one of the biggest influencers Elon whenever he talked about Bitcoin "Btc" moves well I would say he also drives the bitcoin market this year now we are witnessing correction phase. On the other hand, I also believe the demand and supply also drive the BTC value to some extent.

The price of Bitcoin moves according to supply and demand, from the many articles I have read, no one should be able to control the Bitcoin price.
But the fact is that people who own large amounts of Bitcoin can manipulate prices, and what usually has a large amount of Bitcoin are whales.
Because if the whales decide to sell or buy Bitcoin, it must have an effect on the price in the market. And whales can be individuals or companies.

Actually there's no one should control the price of Bitcoin due to the fact that it was decentralized unlike Fiat, however, those persons who own a large portion of Bitcoin which is basically the whales do have a big impact on the market price. Like if they choose to hold their coins, of course, the demand will go up and that would make the price goes up as well, and it will be the same if they choose to sell-off. The next thing I believed that has a major influence on the price is the crypto influencers, remember when Elon mentioned Bitcoin in his Twitter account it surely made hype in the market.