I would not be happy with mouse pointer hijacking. Seems to belong in the same territory as scroll-hijacking but worse. The example case here could have been served by simply highlighting the area of interest in the UI with a red circle or a flashing pointer, whatever does the trick -- even though that may be distracting too.
There are a lot of interactions on a PC where user inputs land in the wrong place.
Claude Code and Codex in their various avatars allow us to type the next prompt while the agent is still working and responding on the earlier one. But this constantly runs into a permission prompt from running session -- either interrupting or worse entering a response to the permission prompt unintentionally.
Even during normal prompting slash commands interfere annoyingly with normal use of the slash key (i use a slash to indicate a list of two or more choices sometimes when i write).
Permission popups and confirmation dialogs that appear unexpectedly and swallow our keystrokes, spacebar and enter key hits mid sentence have always annoyed me.
Laggy devices, and resource hungry sluggish UIs compound this problem.