Oracles development stumbles on a key security feature: trust. Either having a descentralized network of oracles feeding a smart contract or the case of an oracle sourcing info from the web or IoT servers it is critical to be able to verify information source integrity.
Intel SGX can handle runtime encryption and proposes to allow for verification and security of data. Other products (such as AMD SEV) will compete for a similar function in the industry as well. It is likely, however, that a short list of solutions serve the oracle industry.
Maybe such concentration is unavoidable – is it desirable, though? If not concerned, developers should be aware of this feature when designing the single point of failure of entire ‘trustless’ systems.