Widening the Overton window can yield opportunities for ideas that many find offensive, and straightforwardly mistaken, as well as for ideas that are well-defended and reasonable. It is understandable that those with deep personal involvement in these debates often want to narrow the window and push it in the direction of those views they find unthreatening. But philosophers have a professional duty, as conceptual plumbers, to keep the whole system in good working order. This depends upon philosophical contributors upholding the disciplinary standards of academic rigour and intellectual honesty that are essential to ethical reflection, and trusting that this will gradually, collectively lead us in the right direction.
As someone who had a transformational experience during my college years, when I took part in an Honors Program in Social Thought and Institutions that had students in the program reading and talking and writing about "utopia" for two entire years, I have a strong sense that "possibility" is a category much more expansive than the category of the "realistic."
In fact, I am very much opposed to succumbing to the "tyranny of what is," and I'd say that it is high time to push that Overton window of political possibilities as wide open as we can!