Ran this through Google’s Big Query on the two largest political subreddits on reddit.com. The two queries were

SELECT domain,count(*) as Count FROM [fh-bigquery:reddit_posts.2017_01] WHERE subreddit = "politics" GROUP BY domain ORDER BY Count DESC SELECT domain,count(*) as Count FROM [fh-bigquery:reddit_posts.2017_01] WHERE subreddit = "The_Donald" GROUP BY domain ORDER BY Count DESC

Make your own conclusions, but the results are pretty telling for the diversity of posts and their content.