The issue is not time travel per se, but the claim that the aliens are traveling from the future (our/their future) to the present (our/their present) to affect the future (our/their future).
I have no problem with any of the concepts of time travel where “virtual tourists/scholars” (in any direction) get to look but not touch—it is when time travelers start kicking the tires that the craziness starts.
I have seen no coherent explanation of how it is would work without creating infinite kooky time-loops. (In other words, if one alien can do it another one could undo/edit their work ad infinitum...)
“(In other words, if one alien can do it another one could undo/edit their work ad infinitum...)”
Absolutely. And why I believe one entity is protecting us from the other entities and ourselves. But with as little intervention as possible. They are gently steering us towards a progression of historical events that will define their own reality in their present. Yet there are others who would like to derail that future reality.