Is there a long term future in hand-crafted UI/UX? Maybe not.
Is there a future where we still have traditional UX? Absolutely.
I don't want to write a whole dissertation on this topic, so I'm just going to mention that we tried to build AI voice assistants for a decade, and while LLMs have basically solved understanding, they have not solved the UX portion.
Aside from entertainment/marketing purposes, I think UI will become useless. Why should I interact with UI when an agent can (and will) interact with it?