> But it's almost certainly the case that the only conversations that have really mattered have been with electeds themselves.

General public debates with people who disagree do matter a bit because the electeds must believe that there is a group of people who will stand up and defend them (convincingly) from pressure if they take action. A certain amount of background buzz is indirectly helpful.

But yeah, seriously attempting to convince keyboard warriors or hard opponents is a complete waste of time. There often aren't a lot of them and once someone has spent enough time on a topic to adsorb most of the arguments then there isn't any reason to expect them to change their mind later on. Persuasion is for people who haven't formed a clear stance yet and there are occasional rare wins when someone changes their mind although it shouldn't be counted on.