That’s using the default system prompt, right? Which is told to be an assistant.

I might agree, GPT-4.5 was pretty close to peak conversationalist. Newer models are extremely cringe. 4.5 and o3 actually made me laugh on occasion. There might be a way of making Sol/Fable more human in its responses, but out of the box at least, they're terrible.

You're overindexing on the past 3-6 months, IMHO.