It also fits with what we know about her. Janeway was always second guessing her decision to ultimately strand her crew in the Delta quadrant. She felt extremely guilty about all of the people on her ship that got killed through those 20 years (especially Seven of Nine) and wanted to do something about it.

Good points. I haven't rewatched Voyager since the finale aired so I may have been conflating the two Janeways. I'm just going to ignore the obvious time travel issues this raises because they make zero sense.