Most of those things came long before Reddit and still apply to just being online in general. Only the word "subreddit" is unique to Reddit, as well as certain in-jokes ("when does the narwhal bacon?"). Really thinking about it, I'm not sure Reddit was ever really unique at all. It just has a lot of users.
The narwal bacon meme itself was specifically reddit, as it was a deeply cringey joke post someone made as a shibollith to try to identify redditors in the real world.
It was the perfect mix of very awkward, very stupid, and weirdly preening that got people to "ironically" use it for a bit on reddit, which then spread wider.