Humane was founded in 2018, well before ChatGPT was released in November 2022. If you look online you can find some articles about patent applications they made well before ChatGPT was released that give you an idea about their idea for the product at the time, e.g. https://9to5google.com/2022/01/07/humane-android-ar-wearable...
Developing the hand tracking, laser projection system, voice recognition, etc. is very hard, especially considering the power constraints on the device. They spent years working on this and when LLMs hit the scene they realized that the original product idea was going to be severely lacking if they didn't integrate this technology. This caused a big internal pivot to more closely integrate with these LLMs. I'm not sure which they're using, presumably they're paying for GPT-4 access or something like that. It's understandable why they felt like they had to do this, and why it feels like a rushed integration. The bottom line is that they were way too optimistic with the hardware capabilities when they started working on the product, and the last minute rush to integrate with LLMs to at least improve the software capabilities to kind of close the gap is what we're left with. It's not a great situation, but I also think it's unfair to characterize it as a "cash grab".