I don't see anything wrong with discussing ideologically divisive issues, and it occasionally happens here. Rationalism is useless unless you learn how to apply it in real life, and "ideologically divisive" issues are the ones most in need of rationalist analysis.

Take abortion. A rationalist analysis would probably include some known biological facts, some philosophical debate about the nature of consciousness and self, and some utilitarian calculus about trading one life for another.

On an issue like abortion I don't think we could really resolve the political argument by simply sitting down and spending a few days thinking rationally. But this is only because in my own analysis the problem reduces to issues of philosophy of mind and terminal ethical values that are still unresolved in general. But I do think that it would be an extremely useful exercise to see such a highly political issue discharged into a matter of facts, epistemic philosophy, and ethics, rather than tribalism.