A slightly more paranoid me asks whether there’s some magic they’re using that no one is completely aware of. Watching Google fumble around makes me more paranoid that that’s the case.

Have you tried Anthropic LLC's "Claude"? Between it and ChatGPT I'm hard pressed to say which is better, though I'm tempted to give the edge to Claude.

Alpaca on 13B Llama is enough to convince me that it on 65B Llama would match GPT 3.5 for most tasks.

Perplexity AI's app is definitely better than GPT 3.5 for many things although it isn't clear how they are doing everything there.