Hi, thanks for the review!
I do agree that it would be nice if Blender could do it out of the box, though I would hope it would be implemented in a better (and easier to expand) way than how this addon does it.
Good thing is, Blender's developers are already discussing and working on a process dialog system that might make this addon either simpler to extend, or completelly unneeded:
Devtalk forum discussion:
Progress Dialog for Slow Blocking Operations [Proposal] - Developer Forum
Current development:
#139046 - WIP: Core: blocking computation progress information - Blender Projects
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