An interesting theory, it may well be. Especially considering that Bella's path, there are hints that their story is not much different and as we learn in chapter 5, her sister is in a coma. However, I understand the dissatisfaction of many people with this character(Summer). If you look at the experience of other AVNs, the appearance of exes mainly brings a lot of negativity. They seem unnecessary, appear mostly out of nowhere and, as a rule, by this moment the public already has their favorites, so they are rare find interest. All this multiplies if it creates confusion with the feelings of the past MC (plot) vs the control of players who are not very interested in this, at least. Take for example AVN, which I recently played. Leap of faith (?). In some moment an ex appears there, with the storyline that she loves MC, but she has a husband who is very dangerous. In the eyes of the author, there is an interesting plot, the fight for the princess against some powerful guy, so many emotions, so much drama..... ..and this apparently did not find a response from the audience, since this character then disappears for a long time, and then there is some kind of ridiculous story about espionage and the fact that her marriage is a fiction. All this leaves some disappointment. Something similar could could very well happen to Leia's character from Wiab. There are hints that the love path storyline will be somewhat reminiscent of the ex from the mentioned Leap of faith. Then, I would say that Leia has a very high chance of falling from the throne of favorites.
However, everything said earlier contrasts sharply with SG. Here it is in name of Summer that the game is called, her story, her disappearance played a significant role on the MC, her shadow still weighs on him, her story runs parallel to the present and there is a considerable chance that her plot is woven into the main story of the future. And what will come of it, only time will tell.Summer has a difference from the simple *exes* other AVNs.