With AI capable of generating long multi paragraph results, this pattern allows for granular editing control over specific selected text.
While intuitively this pattern may seem more suited to technically proficient users, it's broadly applicable because of how common place it is to review & edit text. Selecting only the third paragraph or the second half of a sentence is an intuitive action for most users.
The key consideration is how granular do you think your users need to edit their results. It's is selection down to the individual letter, word or whole paragraph.
For example limiting selection resolution to whole paragraphs is a balanced trade off between a simple user experience & a meaningful amount of content for the AI to regenerate a meaningful alternative.
Consider also if the regeneration action would be easier for users if contextually relevant pre canned prompts were provided.