What Apple showed seems quite useful. It is a shame they failed spectacularly at execution. Even the simplest things that should be answerable by an LLM and their data, which is what a lot of people want, should be a very low hanging fruit - so much utility without building a complete experience from scratch.
Why cant I just say 'do I have any notifications from a bank?' or 'show me emails that require my attention'. Those things are simple if done with a combination of multiple tools (e.g. feeding email content somewhere, asking it to classify, show the results), yet a three trillion dollar company, with dedicated hardware release just for this purpose, failed to achieve it.
I might be over simplifying things, but with infinite resources, they should be able to do better.