Case: I create a painting with a prompt and when it's done I say: "yes, this represents how I feel, and I want to share it."
What's the difference?
What I always emphasize is that if the input and output are sufficiently divergent then your sense of accomplishment at the resulting creation should be proportionally diminished. But what do I know? People use ChatGPT to write a story and midjourney to illustrate it, then make a viral post with the caption "I just wrote a book in under 24 hours."
The difference is clearly massive.
If someone feels these tools help them express what they want, if they are satisfied, I would call that a form of self-expression. I mean, who am I to deny them that feeling?