As far as I understand, blockchain and bitcoin imply anonymity and decentralization.
However, crypto exchanges now seem to kill these features by KYC procedures, so exchanges know who are their customers, how much money they have at their accounts etc.
Is this right? Will these exchanges exist for a long? How this problem can be solved?
It's a tricky one. Exchanges aren't a part of Bitcoin's design. Once you actually
have some bitcoin, the most secure way to transact is to have one sender and one recipient, with no other third parties involved, so there's no KYC. You also shouldn't be leaving your coins on an exchange once you have them. But again, this is only once you already
have bitcoins.
If you want to
get bitcoins, the ideal way to do that is to meet someone willing to sell you some bitcoin in exchange for your local currency, preferably in cash. But they're not always easy to find. So some people do find it easiest to register with an exchange who accept fiat, but unfortunately, most of them do now require KYC. Even some traders on
localbitcoins (which I'd recommend over centralised exchanges) insist on seeing ID now (which seems somewhat perverse), so even that isn't always a perfect solution. But if possible, try to find someone on localbitcoins who doesn't want your ID.
Failing that, there is a
Currency Exchange subforum here, but be sure to check profiles and their trust feedback before striking any deals to ensure you're doing business with someone reputable. If you can also find a reputable escrow, that's better still. If you see any red text on the trust page, tread carefully. It may also be worth checking the
Reputation boards just to make sure there have been no prior grievances.
Altcoin trading is less of an issue, since decentralised exchanges and atomic cross-chain transactions will eventually put a significant dent in the popularity of centralised exchanges. But bridging the gap between fiat and Bitcoin is going to be problematic for the foreseeable future.