Giving our physical laws I don't see how "observing without interfering" is non-magical. There seems to be a lot of assumption you make about the term non-magical that aren't well founded.
If you only observe by absorbing particles, but not emitting them, you can be far enough away so that the light cone of your observation only intersects with the Earth later than the original departure point. That would only change the past of presumably uninhabited areas of space-time.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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