Yes - not sure if everyone understands this. ChatGPT took GPT 3.5 as a starting point, but then has a reinforcement learning stage on top of that which has aligned it's output to what humans want from a question-answering chat-bot. It's basically the next generation InstructGPT.

https://arxiv.org/abs/2203.02155

From a quick scan of the Bloomz link, that seems to be just an LLM (i.e. more like GPT-3), not an instruction/human aligned chat-bot. There's a huge qualitative difference.