For a very long time, even the largest projects used centralized oracles, the very idea of which goes against the principles on which the crypto industry bases. Objectively, this was a forced measure because most of the trading took place on centralized exchanges. These restrictions led to the emergence of conventionally decentralized oracles like
Chainlink and centralized oracles like
Compound. Aside from centralization, the problem is the lack of economic benefit from independent agents for recording prices in any Price Oracle smart contract.