I think they'll have another LLM on a server (maybe a deal for openai/gemini) that the one on the device can use like ChatGPT uses plugins.
But on device Apple have a gigantic advantage. Rabbit and Humane are good ideas humbled by shitty hardware that runs out of battery, gets too hot, has to connect to the internet to do literally anything.
Apple is in a brilliant position to solve all those things.
I hope they announce something good at WWDC