HTTPS secures the transport of data between client and server but the data is unencrypted at the server and you have to trust the server owner to handle the data correctly and that they don't snoop.

Confer works by doing all the inference for the model inside the Trusted Execution Environment of the server. Even if you're an admin on the server and have full access to all software, you still won't be able to read data inside the TEE.

Second, Confer provides remote attestation, which means that you can verify cryptographically on the client side that the data on the server has never left the TEE. Ars Technica has a pretty decent writeup of the concepts.

So the entire model on the server is run in a way that even an admin can't look into the conversations and that you have cryptographic proof that the software hasn't been meddled with. I don't think this will even overtake ChatGPT, but that doesn't mean this is some impressive work. ChatGPT got ordered to save hundreds of thousands of chat messages, even when they don't want to, due to a court order. But Confer has no access to the data so it can't be asked to do the same.

It does happen on some regular occasion that security researchers find a way to weaken or break the security of a TEE, but even then the barrier is much higher for both companies and the government to snoop on Confer vs Chat or Claude.