So both bitcointalk and r/bitcoin is administrated by the same person but with entirely different agenda with those sites.
theymos has the most control over this forum and the subreddit. But the subreddit mods aren't mods here.
/r/Bitcoin is supposed to be a BITCOIN subreddit. So Bitcoin Cash discussions aren't allowed there. That's what most mods of the subreddit delete (people claiming BCH is the real Bitcoin, claiming that Blockstream owns Bitcoin and it's controlled by the banks, etc...), meanwhile, this forum is more open to this kind of 'trolling' and discussions about BCH/other altcoins.