I think the UI metaphors will evolve over time. I do think terminal UI can get you very far, but as things 1) become more complex, and 2) happen in the cloud/remote machines and collaboratively across multiple participants, I think terminal makes less sense.

These days, something like the GPT/Claude desktop apps are pretty good, where the interaction with agents is front-and-center, but IDE-like UIs can appear when necessary.

I feel like the ultimate IDE is WYSIWYG and visual, while allowing arbitary natural language edits, plus some affordances to view the underlying code artifacts when necessary.