Their are godfathers of bitcoin ecosystem who can manipulate it the way they like. After all someone created it in the first place, Not God. So someone is also there changing and manipulating it the way it suites them. It's a company after all. Its been governed by a certain group of people.

I think, no one can control the Bitcoin system. Its a personal system. The user can only control the Bitcoin she/he is folding.

I think no one can control BITCOIN, even if there is a decrease and increase in price it all happens because of the volume of transactions buying and selling

In your opinion. Which is system?
Bitcoin security system is offered by the purse providers, exchange systems are offered by those who have a market.
But for a price change system for every penny and every second, I think we get involved in it.

literarily nobody has control over other peoples bitcoin but the price of bitcoin can be influenced by people that hold the highest percentage of the coin in their wallet so technically they have control over the price but they don't have control over the activities of other holders of the bitcoin. the same thing applies to altcoin as well. major coin holder can control the price and that is what caused pump and dump of the coin some time because the price has been influenced

One of the common concerns of other people here is the bitcoin system because the most questions is the person who's manipulating the bitcoin. Experts keep on saying that it is anonymous but the scary thing that other think is that what will happen if there will be a corrupted at the protocol level. Indeed, it is programmed, but as far as I know it is anonymous.

Bitcoin and blockchain is being introduced as a decentralized system that everyone holds their own ledger so it means it doesn't need a third party like bank. So its impossible that anyone can control it thats why many country are making a regulations on how and where to use bitcoin and altcoins.

Technology and the bitcoin system is decentralized. But I do not rule out the fact that digital currencies can be managed by someone.

Bitcoin does not belong to anyone. This technology can be used by anyone who follows the rules of this currency.
It is not controlled by any central bank, and the person who first proposed the use of bitcoin for several years does not make itself felt.
Everyone can make sure that this currency does only what it is supposed to do, and its creator no longer controls operations with bitcoins.
Now it is the responsibility of independent developers. That is, bitcoin has become a so-called open source software, which can be downloaded and used for free at your own discretion.

Noone controls Bitcoin system at all because it was built by the blockchain system and there are only blocks in this system not controller.
The only thing you can control in Bitcoin is the price which is very insane in every moments. Sometimes it was dump and sometimes it was pump but invest in it will be profit all the time.