It needs to be at least this long. They need to be in the doghouse for a really, really, really long time for the way they have embraced fascism. Honestly, it would be nice if "GOP" just became synonymous with "Facist, White Christian autocrats". I'm not sure they understand how stupid Project 2025 was for them. They are going to have that anchor thrown around their neck for the next two or three elections at least. Maybe longer. "no no, I don't support that at all! I don't even know what it is!" "Well, do you really want to risk that he's not just saying that to get you to vote for him?".
With luck, a new Party will form that will include all the alienated Republicans will form. It might be the only way to get rid of the Project 2025 label.