This question is ambiguous because both “social media” and “debate” are general terms that are not clearly defined in daily use. So, I am going to offer my two cents on this issue by clarifying my thinking around these two terms.
First, what is social media? This general term refers to many platforms that are designed to support different types of communication. Based on Wikepdia, social media are “computer-mediated technologies that allow the creating and sharing of information, ideas, career interests and other forms of expression via virtual communities and networks.” The immediate examples are Facebook, Twitter, and Reddit, from which we easily see clear differences. In particular, Twitter is designed for effective information propagation. The 140-character limit requires a user to speak succinctly. It is thus difficult to develop an elaborate discussion.
In comparison, reddit allows users to self-organise into communities and some communities are able to maintain a healthy environment for constructive discussions. Take /r/changemyview for example, in this community, open-minded users who want their opinions changed explain why they hold the opinions and invite other users to provide counterarguments.
https://www.youtube.com/embed/OU-YZm5gDQ4?wmode=opaque
In this way, many people become informed about the opposite views and even change their opinions eventually. My collaborators and I wrote a paper to explore interaction dynamics and persuasive strategies particularly on this community.
Now that I have shown how the patterns of communication vary across social media platforms, I am going to explain how “debate” differs by its goal and format.
Users on social media can participate in a debate with completely different goals: one may try to hear counterarguments, whereas another may want to simply vent his rage.
Users on social media can participate in a debate with completely different goals: one may try to hear counterarguments, whereas another may want to simply vent his rage. It becomes impossible to “debate” with such drastically different intentions. Regarding the format, a debate on social media usually takes place in the comments.
However, opposing arguments are not always clearly laid out. One may start a long rant without knowing where another person is coming from. In contrast, /r/changemyview can make sure that community members are on the same page because 1) users come with an open mind, 2) users explain the rationales behind their opinions, and 3) top-level comments are used to provide counterarguments.
In such contexts, it makes sense for users to think about how one should phrase an argument and what we found in our paper, correspondingly, is that wordings that use different words from the rationales of the original opinion correlate with effective persuasion.
In summary, I do not have short answers about the best way to “debate” on “social media”.
However, I find it useful to be mindful of what kind of communication we are promoting and how we can communicate effectively, both by maintaining an open-minded community and by understanding how to use our language appropriately.