I think they've been trying to change that recently; they've been focusing more on content creators - people like Shitty_Watercolour who are known Reddit-wide for the original content they post. As you noted, they launched a new type of profile which basically turns it into a subreddit, which they're pushing as a way for content creators to post their works easily.[0] The feature is still being developed but is now available to more people.
To me that feature just looks like a way to add RSS/ RSS-like functionality to links a user wants to share or posts a user has participated in... it can be used for self-promotional purposes, but it doesn't have to be.