To me it is just usual Firefox behaviour chasing some trend or other. Adding features for sake of adding features. I wonder what is the over-under when this feature will be deprecated...
If this was them bringing over window.ai from Chrome I'd say it would be good. I love the offline translation they added, and wouldn't mind something similar for LLM. But having a separate panel that's just basically chatgpt & co isn't impressive.
I'd much prefer an offline capable, leaner LLM that lets web devs do cool stuff.