What makes it irrational? The reaction to betrayal? Letting down people who would have otherwise been employed by the production? That could be selfish. Giving up the income he would have made from the film? Selling a book instead of a movie?
If irrational means a lack of reason, his reason is clear. If it means a decision made in haste, you may have a point - but that's not irrational and there is still a reason, whether it's emotional or logical. Both are equally valid for human beings with feelings.